Confessions of a researchaholic

November 1, 2019

Deadline ruining your holiday?

Filed under: Real — liyiwei @ 4:24 pm
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I never understand why people want to complain about how deadlines ruin (their specific) holidays.
Everyone is free to finish the job before the holiday even if the official deadline is afterwards.

I remember Hugues Hoppe told me that he usually had a complete draft of his submissions before late December, and in one instance he didn’t even touch the paper between X’mas and the January deadline.

Nowadays, one can submit to ToG anytime and still present in SIGGRAPH; I am not sure what is the real difference. And there are other related venues like CHI or CVPR.

Personally, SIGGRAPH crunch is kinda fun for me, so I won’t mind one way or another.

August 23, 2019


Filed under: Real — liyiwei @ 4:56 pm
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A co-author added a typo “SIGGRAPHickness” into a bib entry today; I guess it means sickness induced by working too hard for SIGGRAPH.

August 4, 2019


Filed under: Real — liyiwei @ 4:20 pm
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I spent most of my time in the experience hall with the workshops and demos.
I did not attend a single paper session.
I could socialize with the paper authors a bit more, but I bump into some of them in the parties.
The more conferences I have attended, the more I believe the value of hands-on experience in trying out new things and interacting with different people than just passively listening to talks (most of which are recorded for later viewing, except for the movie production sessions).

For the entire week (from July 25 to 31) I had dinners in various parties (SIGGRAPH Asia technical papers committee meeting and SIGGRAPH conference).


The cybersickness workshop sounds relevant to my research. When I went there, I saw a presenter talking over slides full of dense texts and felt sickness without HMD already. So I left.

I know about the turtle visual programming, but this is the first time I tried hands-on with the Turtle-Stitch embroidery machine.
Basically, you control the turtle (pointer) movement via blocks and write a program by chaining the actions together. Warnings will show if any step may cause manufacturing issues, such as large strides. The program can be saved to a weaving machine to produce an embroidery.

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TurtleStitch embroidery – wow smiley face

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The VR/AR magic session much more interesting with several talks from the industry.
For stationary players, locomotion in games can be achieved via hand controllers for speed and turn.
Synthetic blinks in the rendering can be added for teleportation and turn without eye tracking.
Magic Leap presents Mica, which looks very realistic during the presentation which made me wonder if the company is considering pivoting towards content creation if the hardware does not pan out.
I made a mental note to try the demo to see how opaque the graphics really is.
Mica can be animated with the geometry model plus helper joints.
Particular emphasis is on gaze and attention simulation to focus on face social triangle for face and saccade simulation.
The game porting talk is boring to me so I did not pay much attention.
The sonic immersion talk is very good; the two presenters skillfully use non-VR demos to demonstrate the importance of sound effects for immersive ambisonics.
More information can be found about ICTUS audio.

I went to lunch at Cow Cafe (a vegetarian place near the LA convention center south hall). The egg scrambles were good.

I spent the entire afternoon in the immersive pavilion.
Heterotopias performs cinematic cuts during blinks; the idea sounds very interesting but the demo does not really work for me as my glasses might have prevented accurate eye tracking.

I forgot that I actually had no paper in SIGGRAPH 2019 and thus would have to come into the papers fast forward with everyone else, and ended up sitting on the first row.
I had some quasi-dinner in the Beijing academy and Taipei parties afterwards.
I bumped into Kurt and recommended him to look at the Shard/Glasswing demo; he said that by nature he will ask a lot of pointed technical questions, and I told him that Gavin would be there to answer.


I went to register for the Mica demo, and bumped into Zhenyi in the queue. She mentioned as a related work.

I could not get into the NASA VR session, so I went to the experience art talk (AI and embodied experience) instead.
Lavin trains a junky neural network to output limited vocabulary for a person image, and renders the corresponding 3D shapes in VR.
The hugging sculpture photogrammetry is also interesting.

Cow Cafe ran out of materials for scramble eggs, so I ended up with a less tasty avocado toast. I guess they also ran out of arugula and gave me romaine lettuce instead.

Mica demo has interesting interactivity, the graphics is not as opaque as it should be (as I expected) but it is ok. I did not try to go off the script as the aim is visual not interaction. But I still managed to break the demo in 10 seconds.

On my way to the keynote Johannes told me it was really bad and unprepared. It is unscripted, but not as bad as he commented. Sometimes we can learn more about the speaker from a spontaneous talk.

The Spheres VR movie is very good; Darren Aronofsky is listed as a contributor.

The de-noising session looks interesting so I went there.
Color space sculpting seems like a simple and effective idea for color edit.
I doubt how general the neural-network de-speckle approach can be.

When I arrived at the NVIDIA party after the only electronic theater show, the hotel staff was already starting to take away the food.


I went to the After Effects creative medium workshop. I cannot really follow due to small display text but managed to experiment with the tutorial file a bit to get the gist (usual scripting and compositing stuff over the video time line).
Basically, there are people using Ae purely for synthetic effects instead of video post processing.

I then went to the hardwearable session.
Missed most of the NVIDIA AR eyeglass talk.
The electric control plastic haptic device looked interesting and I made a mental note to try in etech.
Artificial tail and temperature control auxetic are also interesting.

The interactive street art AR workshop is fun and reminded me about Aero authoring.

Real-time live was fun as usual. Hair VR did not win the best show but Liwen and Hao did a great demo (with Jun’s head).

I skipped the Stanford reunion and went straight to the Facebook party; the venue is great!
After giving my drink tickets to Kari, he told me that the Stanford reunion got great drinks.

I did not manage to attend the Adobe party before closing.


I spent most of the morning in the VR demos.
The guy in the autism AR app told me about how png used to support vector graphics.
The OVS + tumor VR app looked and interacted very well.
The VR redirected walking space station demo (Frank Steinickie) worked very well by simply using highly occluded environment with task distraction without even leveraging blinks or saccades.
The unreal workshop is fun; one can place geometry scene structures for a character to move around for a simple game level.
Being Henry VR movie with gaze and blink control works very well and realistically simulates the situation of someone who could not move except with eyes and a hand.

After accidentally attending the women lunch in UIST 2016, I bravely attended the Berthouzoz women lunch in SIGGRAPH and even more bravely volunteered as a discussion leader.
The speakers were inspirational but I had to cut short the lunch to attend a meeting with Illustrator guys coming all the way from India.
The meeting was very productive and I managed to come up with four potential projects.

The DreamWorks party got good food; it took place inside the convention center, so very easy to attend.

The game of thrones production session was fun even though I never watched the show.
It was too late to attend the Snap party afterwards, so I went to the Apple party. The Canadian party was right around my hotel but I was too sleepy to go.


I got up early for the Glasswing talk session at 9 am, and tried some VR stuff afterwards, such as T-Rex assembly, beach muscle building, etc.

I did not realize the physical pad (Bamboo) is actually linked with Wacom Inkspace, and had a great time experimenting with the hardware.

Autodesk fusion 360 create cad shapes to guide drawing in sketchbook, I got the idea even though I could not create complex shapes.

I bumped into Jonash and lunched with him in Cow Cafe (which kindly gave me a discount code).
I had to miss the Alita production session for flight, which was delayed for 2 hours. I plan not to cut short of the conference in the future unless I really must fit a flight schedule (not between LAX and SFO).

TODO: checkout the blackhole talk, which people told me was great and should be the keynote. Why they put these really interesting forwward looking stuff in the early mornings?

September 16, 2018

MSR Asia single-author challenge

Filed under: Real — liyiwei @ 4:32 pm
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It has been 10 years since I posted up the single-author SIGGRAPH paper challenge to MSR Asia, and nobody has managed to claim the prize as far as I know.

Looking back at my writing, I was wondering who this blunt prick is.
If I could, I would tell my past self to be more graceful without compromising the strength.
Otherwise, I still stick with, and have faithfully followed by own edicts, after switching into these other roles.

August 20, 2018

Shadow QA

Filed under: Real — liyiwei @ 2:41 pm

During the QA after each paper presentation, it is common for the advisers to help the students, especially first-timers, to answer (or translate) questions.

I used to sit on the stage, which I dislike as the bright podium light can shine directly into my eyes. I once shielded my eyes with a hoodie, and people commented that I looked like a gangster.

Then I switched to sit on the front row and step up to the podium during QA. People can see my face; I prefer to remain invisible.

Finally, this year one of my papers was presented in a large, dark ballroom.
A narrow light beam casted over the speaker and the podium was right on the edge of the stage, which allowed me to sneak aside without being seen.
This is my favorite stage design so far.

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August 16, 2018

The coolest I have seen in SIGGRAPH 2018

Filed under: Real — liyiwei @ 7:39 pm

Coolest demo in real-time live: AI + animation in addition to sketch-based modeling in Teddy

Very cool VR format for anime/manga by Square Enix

Coolest exhibition: the looking glass autostereoscopic display, the game demo, for the first time, made me think that consumers might finally want to buy a 3D display at home.

Looking glass display

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August 10, 2018

成功地將作者漢字姓名塞入一篇 SIGGRAPH 論文

Filed under: Real — liyiwei @ 3:47 pm

After years waiting for the right combination of paper format and authors, I finally managed to insert 漢字 author names to a research paper which now resides in the ACM digital library.

October 25, 2017

Voucher code

Filed under: Real — liyiwei @ 5:12 pm

[Update] The code went to Tejas Shroff, whom I don’t know but who seems to be doing interesting VR stuff.

September 8, 2017

Expresii appy hour

Filed under: Real — liyiwei @ 5:03 pm

My friend Nelson Chu could not attend SIGGRAPH 2017 to demo his Expresii, so I stood in for him.

Thanks to the wonderful product from Nelson, this is a fantastic presentation experience. I can interact with and talk to many different people, focusing more on practical utility than technical details. I had no time to get bored for the entire 2-hour duration. People kept on visiting even after the session closing. And I had a great time practicing playing the app myself.

Publishing a SIGGRAPH paper is about proving how smart we are, while demoing a SIGGRAPH app is about demonstrating how useful it is for you.

August 22, 2017

ACM author rights

Filed under: Real — liyiwei @ 10:09 am

Among the 3 options for your glorious SIGGRAPH (or other ACM) paper, I usually choose the new licensing agreement (option 2) because it does not require shelling out a few grands for retaining all rights (option 3) and allows the authors to retain the theoretical copyright unlike the traditional copyright transfer (option 1).

By theoretical, I meant that options 1 and 2 probably make little to no practical differences for authors, since the license transfer is perpetual and exclusive for ACM, and authors can share their preprints anyway.

August 11, 2017

Servers down

Filed under: Real — liyiwei @ 10:45 am

Hmm do people start to submit so early for the next SIGGRAPH?

Server is unavailable

Please try back later…

The SIGGRAPH server is experiencing very heavy traffic right now, and cannot service your request. Please contact if you need immediate assistance. Otherwise, please try your request again shortly. Thank you.

[Later] And this:

July 28, 2017

SIGGRAPH 2017 parties

Filed under: Real — liyiwei @ 5:15 pm

9 to 11 pm, Sunday July 30 2017
L.A. Live Courtyard & Residence Inn, LA 2 & 3

6:30 – 9:30 pm, Monday July 31 2017
(Invitation only)

6 to 8 pm, Monday July 31 2017

Disney (?)
Dreamworks (?) (?)
GVU (?)

5:30 to 7:30 pm, Wed August 2 2017
4th floor (outside) Bonaventure Brewing Co. 404 S. Figueroa St

Canadian night
9 pm to midnight, Wed Aug 2 2017
Shoo Shoo, Baby, 717 West 7th Street, Los Angeles, CA 90017

August 18, 2016

Milestone of seniority

Filed under: Real — liyiwei @ 1:09 pm
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March 11, 2016

Conversation with collaborator X prior to a SIGGRAPH rebuttal

Filed under: Real — liyiwei @ 1:11 pm
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X: I’m really eager to see what the SIGGRAPH reviewers have in store for us this time… The suspense is killing me. =o

Li-Yi: I just assume they will screw me, and I am never disappointed. 🙂

X: Yes, that’s what I do as well, but I’m always amazed about how they always find ways to complain about the stuff you don’t expect. 😮

Li-Yi: If I can expect what others will think, I will be like some sort of x-men or superman. 🙂

October 26, 2015

Autocomplete hand-drawn animations

Filed under: Real — liyiwei @ 9:00 pm
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[This post is for answering press inquiries about our SIGGRAPH Asia 2015 paper titled “autocomplete hand-drawn animations”.]

On August 2014, Koji Yatani (at the University of Tokyo) asked me (on Facebook!) to recommend students for a MSR Asia internship under Takaaki Shiratori with topics in animation and sketch UI. I recommended my HKU PhD student Jun Xing, who just got a paper in SIGGRAPH Asia 2014 titled “autocomplete painting repetitions”.
(Both Koji and I were with MSR. That is how we got to know each other even though we have no overlap.)

Our initial goal was to help users create animated emoji in instant messaging. I wanted to make sure the project is significant enough (e.g. for SIGGRAPH) while leveraging our collective expertise as much as possible. Thus, I proposed to extend the aforementioned SIGGRAPH Asia 2014 paper, which can autocomplete only single-frame drawings, for multi-frame animations. The main goal for both projects is to help ordinary users draw as easily and effectively as possible.
(My dad is an artist, but I have yet to learn how to draw. So as any decent computer scientist would do, I ask algorithms for help.)

Jun designed most of the user interface and algorithms, and implemented the entire system. He is definitely one of the best students I have worked with.

We plan to ship prototypes of the system to gather user opinions for further research and improvements, starting with mobile apps followed by desktop versions.

Contrary to what some press reported, this is NOT a Microsoft technology or product (at least not at this moment of writing). None of the authors were with Microsoft during the key stages of the project development. In particular, the core ideas were conceived before the start of the internship, and Jun had to come back to HKU to finish the project after Takaaki left Microsoft about 1 month before the paper deadline.

July 20, 2015


Filed under: Real — liyiwei @ 11:47 am

I have heard enough saying that SIGGRAPH Asia simply accepts papers rejected by SIGGRAPH, and thus is of lower quality.

This is not my business and in any case I do not care an iota what others think. But any scientifically questionable statement deserves to be rebuked.

Both SIGGRAPH and SIGGRAPH Asia have similar acceptance rates, and are hold at the same review standard in my personal experiences (as authors, reviewers, and committee members).
If you have ever reviewed a SIGGRAPH Asia submission you probably have received instructions from the paper chairs about holding the same quality bar as SIGGRAPH.

In my personal record (up until SIGGRAPH 2015), I have 4 papers rejected by SIGGRAPH Asia and accepted by the next SIGGRAPH, and 4 the other way around. So it is about the same.

The real difference lies not in the quality bar but the (geographic) venue.
As a presenter I do prefer SIGGRAPH due to the usually larger audience.
But I also know others who prefer SIGGRAPH Asia due to visa and travel issues.

December 11, 2014

Street credit

Filed under: Real — liyiwei @ 6:55 pm
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Coauthors revealed a secret in a recent paper that gave us all street credits.
(It is in plain sight for anyone to see, so I won’t tell.)

October 13, 2014

How to make a SIGGRAPH paper

Filed under: Real — liyiwei @ 11:08 pm
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There is a course in the upcoming SIGGRAPH Asia 2014 conference on how to make a SIGGRAPH paper.

The content has not been completed decided. If there is anything particular you like to hear about, feel free to leave a comment below within the next 13 days. You can do so with anonymous or real identity.

Please also help spread and share this.

December 23, 2013

Dear Asian students

Filed under: Real — liyiwei @ 6:10 pm
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Not having to observe Western holidays is your competitive advantage. Don’t squander it.

July 26, 2013

Laptop-less in Anaheim

Filed under: Real — liyiwei @ 3:30 pm
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I did not bring my laptop to SIGGRAPH this year to discourage myself from working inside the convention center or the hotel room.

Experimental results indicated that this motivated me to spend more time hanging out with people, which is supposed to be the main goal for a conference. I can easily schedule all events and meetings via my smart phone and tablet. (Even the tablet is probably not necessary, if I can address a few technical issues of my phone.)

I probably would have had to bring my laptop if I had to give any talks. None of the Android apps I know of can adequately author talk slides. If such apps eventually show up (and I expect they will), I would happily travel with only my phone in the future.

Eventually though, the phones will likely become powerful enough for me to work inside the hotel rooms (again).

July 18, 2013

Managing paper committee meeting

Filed under: Real — liyiwei @ 3:38 pm
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Most paper committees I have served have purely electronic review processes. These are relatively easy. Those with in-person meetings (e.g. SIGGRAPH) are more challenging as they involve live human interactions in real-time.
Below are some of my personal experiences to make the process more fun and effective.


The most important and yet difficult task is to remain neutral, no matter what happens. It could be quite some experience to see your paper getting rejected and immediately you have to discuss a paper you reviewed.

I have a very simple strategy that works superbly well for me so far: I just assume all my papers are (or will be) rejected, even if they have very high ratings. (Anything could happen, and has happened before.) By assuming the worst case scenario, I can never be disappointed. I also do my best NOT to track my papers; I did not even look at the status on the spreadsheet when I am outside the room. Then it is easier for me to remain cool.

It also helps if you naturally care less.
One possibility is to not have any submission, but this is not common for people who are still productive.
Another possibility is to have enough prior papers so that you care less.
The paper chairs like to recruit more senior people not only for experiences but also for this “care less” factor.

Other things being equal, it is usually better to be positive than negative. My rule of thumb is to accept if unsure. This is better for humanity; a good paper wrongly rejected will not be read by anyone, while a bad paper wrongly accepted will likely be ignored by future research anyway. This is also better for myself; I do not want to leave a reputation for being a paper killer.


It is a lot of work to review 20-something papers. You will look bad if you do not seem to know what each paper is about, especially during the plenary sessions or breakout discussions. So make sure you put in enough efforts.

I also keep enough dark chocolate around to maintain my brain function at the end of the (long) day. (OK this is probably some lame excuses; I overdose cocoa no matter what.)

I am probably lucky (or maybe I am good at requesting papers; dunno yet) in that I usually get good assignments (high quality submission fitting my interests and expertise well), so I usually know each paper well. For those few that are outside my expertise, I just admit it to other committee members and reviewers. Nobody knows everything, so honesty is often the best policy.
Plus, I guess many of you have seen reviewers who clearly have no idea what the f*** they are talking about, so try not to be such jerks.


For those of you who think the committee members have some edges in getting their papers in, you might be disappointed; as far as I can tell, no such advantages exist, and the system has been well designed so that it is very difficult to game.

However, the committee members do have advantages in organizing the paper sessions, which is also the most fun part of the committee service in my opinion. You can influence where and when papers (including yours) go and which sessions you chair. People who do not show up might find papers (they authored or reviewed) going to a strangely titled session with a motley collection of seemingly unrelated papers, or find themselves chairing sessions that are too early for many people to wake up or too late in the last day for many people to remain behind.

June 2, 2013

How to do a paper fast-forward

Filed under: Real — liyiwei @ 12:39 am
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Giving a good paper presentation is already hard, but at least you have 20 minutes’ worth of wiggle room. Giving a good paper fast-forward is even harder, because you have only 40 seconds. Even one tiny mistake can ruin you.


The most common mistake is trying to explain too much (I like to call it “geek’s asymmetry”). Trust me; almost nobody will care, and certainly nobody will understand, within 40 seconds and among 100+ presentations.

The fast-forward is pure advertisement with one main goal: get people read your paper and attend your talk.
On top of that, if you are really good, show what a cool and interesting guy you are. But do not even try unless you are absolute sure. (A good rule of thumb is this: are you already cool and interesting?)


Write down the script first, so that you know what you want to talk about and you can comfortably utter the sentences within the limited time frame. Practice and rehearse a sufficient number of times, especially if you lack verbal proficiency. Only design your slides after the script is in a stable condition. This is extremely important. If you do it the other way around, and I know this is what most people would do, you are making a grave mistake, because (just like what movie critics would say) you are letting the effects get in the way of the substance.

Do not force people read your slides. Use pictures and animations instead of texts to explain your points.


After having both the script and the slides, practice, until you can do it perfectly during sleep.

March 15, 2013


Filed under: Real — liyiwei @ 4:22 pm
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A recent PhD graduate whom I know well, who has been doing quite well in graphics research, just took a non-research job in a non-graphics position, among several postdoc offers from top research institutions.

The reasons he cited are numerous, but the 2 main ones are:

. He likes graphics research, but he is getting bored and tired of the SIGGRAPH game, including deadline crunch and dealing with reviewers.

. He would like to learn something new and try a different life style.

In a nutshell, I think he is burned out. I hope I have done my best to help him achieve work-life balance (I did that quite well myself, even when I was a grad student), but I guess it is just too hard for normal people to be much disciplined.

Then I realized that I probably also had some kind of burnout around my graduation. I took a non-research position as the first job, even though it was in a graphics company (NVIDIA). I also wanted to try learning new things (hardware architecture) and living a different style (engineer).

So I guess it is probably OK. People are not meant to be doing the same thing all the time. This is also why I like to try different job sectors and geographical locations.

There are two things to watch out, though, all based on my personal experiences: passion, and rust.


I have a very simple rule to choose jobs: do what you really like, and be very good at it.

Sometimes, when people get burned out, they might temporarily settle for something that they neither really like nor really be good at. But eventually, you will know if the job is not for you. I did not realize how much I like doing research until after I was not been able to spend enough time on it for about 3.5 years after my graduation.

The important thing is to get out there as quickly as possible. Otherwise, you will eventually become one of these people who are not really happy or good at their jobs but also cannot quit.


People tend to get rusty for skills that they have not practiced for a while. This is particularly so for advanced skills, like research.

So, make sure you do whatever you can to be active in research during your non-research job. Otherwise, you might not be able to come back, even if you want.

I have been trying my best to be engaged in research during my NVIDIA days. I even managed to publish a single authored graphics hardware paper. But it still took me about 2 to 3 years to get back in shape for SIGGRAPH after joining MSR. The difference between SIGGRAPH and other graphics venue is like the difference between playing professional sports and working out in a gym.
I guess SIGGRAPH is probably an extreme case, but I hope you get what I mean.

January 7, 2013

Sharing code and data

Filed under: Real — liyiwei @ 1:08 am
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It is usually a very good idea to share the code and data along with our published papers. This will make it easier for others to test, understand, reproduce, and compare against our methods, which in turn can make us more popular, our papers more widely cited, and our technology more likely to be adopted by the industry and turned into real products.
Code and data repositories are also an important part of evaluating job applications.

(I have open sourced most of my first/single-authored projects, except my first 2 SIGGRAPH papers for which I could no longer find the code in the school server, which I greatly regret.)

Ideally the code should be in high quality, but even if not, sharing it can let others have a chance to improve the code (and motivate us to write good code).
It is fair to say that the code and data are no less important than the paper.

Some things to watch out for include institutional and legal constraints, such as trade secrets, copyrights, and patents, and not yet published future ideas.
These can be planned and managed via different git branches (e.g., a public branch that is gradually merged from a private branch).

December 31, 2012

How to design demos

Filed under: Real — liyiwei @ 9:51 pm
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In a nutshell, a demo should properly demonstrate technical aspects with sufficient artistic appeals.

The technical part is usually more important, and can suffice alone for many science and engineering disciplines. However, the artistic part is also very important for graphics and HCI, or any fields which involve direct human perception and consumption.

Demos usually take a lot of time and efforts, on top of the usual workload in ideation, writing, algorithm, implementation, and experimentation. And whether you like it or not, a solid and novel algorithm cannot be adequately assessed or appreciated by the readers if it is not demonstrated through proper demos.

Thus, designing demos is kind of an art. Below are recent suggestions from Sylvain Lefebvre which I have found to be excellent.

A guideline that worked fine for me is to consider whether 1) the result demonstrates the technique properly and 2) the result looks just good enough that it appears useful; in particular we want to avoid people think that the example is contrived to only show the advantage of our approach.

The problem is that 1) and 2) sometimes compete with each other (e.g. a fantastic rendering possibly making it hard to properly see the motion, etc.). Also we do not want to spend too much time on 2), only enough that people will think that it is convincing.

November 10, 2012

How I work with each student

Filed under: Real — liyiwei @ 11:34 am
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This figure illustrates how I collaborate with each student.

There are several main layers of a research project: idea creation, algorithm design, system implementation, and experimentation + results production. They are all wrapped up and glued together by presentation, which includes paper writing, video production, and (conference) talk.

For a beginner student, I would expect you to completely take charge of the implementation and production (including video), given the main ideas and algorithms as described in a paper draft (as part of the presentation). We could discuss anything you like, but you should be able to handle all the implementation and production details (e.g. I am not supposed to look into your code). Otherwise, you are not ready for research.

As you progress, I would expect you to be able to take charge more tasks at the higher layers. Idea creation is the most difficult and only a few can pull that off, but my experience is that a decent senior student can at least take part in algorithm design and paper writing.

September 8, 2012

How to manage project progress

Filed under: Real — liyiwei @ 11:26 pm
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Managing project is a huge topic that involves multiple aspects. This post focuses on one specific aspect, on how to manage and ensure progress. To me this is the most important aspect, because a project that is not done is worth nothing.

My strategy is very simple: use schedules to manage progress.

Here is a quick example.

First milestone demo: October 17, 2012.
(A milestone is a demo that can show the project (1) is of SIGGRAPH potential and (2) is likely to be completed.)

Demo production (assuming we have 3, each with complete and concrete descriptions):
. Demo 1: November 1, 2012.
. Demo 2: November 16, 2012.
. Demo 3: December 1, 2012.

First complete paper draft: December 17, 2012.
(SIGGRAPH is not just about getting things done; it is a refinement progress towards perfection. My hope is to have a one month margin, even though few of my projects, mostly first authored by myself, have made this.)

SIGGRAPH 2013 deadline: January 17, 2013.
(Hard deadline; everything has to be done before this.)

The schedule should be drafted, usually by the first author student, in the beginning of the project, and constantly updated and maintained throughout the project progress. All team members will look at the schedule and agree with its content.

The most important part is to make sure you actually meet your schedule. Do not let anything slip. Otherwise, it will not work.

Of course, research, or any project, can and will bump into unexpected snags. It is also not possible to accurately predict the amount of time needed for every item. The key is to keep the schedule as accurate as possible. For example, if you originally think demo 2 above will take only 2 weeks but it ends up taking 3 weeks, you should question whether you are too optimistic about your schedule and allocate more time for other items.
(If you find yourself not being able to meet the deadline, it means you probably have to speed things up by either working harder or working more efficiently. But the good thing is that you realize this early rather than late.)
As you become more experienced, you will also become more accurate in managing and predicting schedules. Without this practice, you will less likely learn this very important life skill.

I guess it probably very hard to fully comprehend what I mean here. If you are my student, you will learn this through a lot of practice with me.

I learned this through my NVIDIA days. One thing I find particularly proud about NVIDIA is that to my memory *not a single product* has ever been delayed during my stay. This was in sharp contrast to ATI, the (then) fierce competitor to NVIDIA, which (for reasons I do not know) constantly bumped into product delays. The rest is history.

The way the NVIDIANS did it is like this. Everybody and their brothers used schedules to manage progress, and slipping a milestone is considered a more serious crime than shooting someone. The CEO dropped in group meetings constantly and unannounced, and called out those responsible for delays. (Trust me, you will prefer being shot rather than getting called out.)

I like to list one most important thing I learned with every one of my jobs. And for NVIDIA, it will be project management. I do not think I will have learned this if I started as a professor immediately after school.

July 19, 2012

Should you do that rebuttal?

Filed under: Real — liyiwei @ 4:06 pm
Tags: , ,

See here for the related post about how to do a rebuttal.

Again, this is mostly for SIGGRAPH, but likely applicable for other publication venues.

My answer is absolutely yes, for a very simple reason: the amount of time and efforts you spend on rebuttal will be a small percentage of what you have spent in submitting the paper (4 days versus months if not years). Thus, you have everything to gain, and little to lose.

More reasons:

. Review is a highly stochastic and unpredictable process, and nobody knows what is going to happen. I have seen papers with strong rating (e.g. > 4) rejected, and weak rating (e.g. < 2.8) accepted. (And yes, both are mine. And I was told the latter is a SIGGRAPH record.) . Not submitting a rebuttal is usually perceived by reviewers as a (negative) sign that authors agree with their (negative) comments. . Rebuttal is a good practice for both research method and emotion control, especially for students, junior researchers, and myself. . Show you get balls. As a reviewer I admire authors who can manage to come up with strong rebuttal even for a paper with low ratings.

March 26, 2012

Another data point

Filed under: Real — liyiwei @ 1:49 am
Tags: , , ,

In responding to my earlier post, a very talented graphics researcher has shared with me his statistics, as shown below.

As you can see, his has much better success rate than me, especially considering that he has been doing rendering, a tough field for SIGGRAPH. 🙂

March 24, 2012

Fooled by randomness

Filed under: Real — liyiwei @ 11:41 pm
Tags: , , , ,

Feeling down from some recent rejections? I hope this post will make you more positive. The gist: never, ever, quit.

Assume you are throwing N loaded dices, each with a probability p for coming up head.

Now, if p is greater than 0 and smaller than 1, there is always a chance that the N dices will come up with all heads or all tails. And the smaller the N value, the more likely for such extreme cases to happen.

This is all pure chance. But unfortunately, human brains have difficulty accepting randomness, and always want to impose determinism, e.g. patterns or rules or causalities.
For example, if you are a scholar submitting N papers to a conference, you will likely consider yourself to be very good/bad (or the paper committee has treated you very well/badly) if all N submissions are accepted/rejected.

This human fallacy is brilliantly illustrated by Nassim Nicholas Taleb’s book “Fooled by Randomness”.

However, even without reading that book, I can recommend a very simple remedy: law of large numbers. This is a well-known mathematical theorem, which says that the expected value of a random variable can be more accurately predicted by averaging a larger number of samples.

So, for example, to measure your intrinsic paper acceptance rate towards a specific conference, you can take the total number of acceptances divided by the total number of submissions. This will be a much more meaningful measure than your acceptance rate for a single year, especially if you have a sufficient number of submissions across multiple years.

For example, the plot below shows my cumulative acceptance rate for SIGGRAPH, the top venue for computer graphics and interactive techniques. As you can see, the rate seems to be gradually converging to a certain value, around 0.34. This is much more stable measure than my yearly rate, which can be anywhere between 0 and 1.

Now, if you are new to a field, your rate will have a higher variance, just like the initial portions of mine. I was lucky that I had a good start which boosted my confidence. (Initial condition is actually very important and has been found to greatly influence the performance of many careers, e.g. hockey players. Note to myself: dig out that book/article. I guess it should be Geoff Colvin’s “Talent is Overrated” or Malcolm Gladwell’s “Outliers”.) However, if you happen have an unlucky start, do not give up too early; hang on for a while, so that you can have a chance to see your *intrinsic performance*.
As you can see, my intrinsic performance did not really show up until about a decade doing SIGGRAPH.

(With all these rational arguments, I have to confess that it still hurts to get rejected!)

Some notes about the graph: (1) I plot SIGGRAPH at integer years and SIGGRAPH Asia at integer + 0.5 years, (2) missing data points are for years which I did not submit anything (2004 and 2005 while in NVIDIA and 2011.5 when I have nothing to submit for SIGGRAPH Asia 2011), (3) a more accurate measure would be “moving average” (with exponential decay of past values) but I probably need another 10 years to warrant this, (4) I really want to improve my intrinsic rate to at least 50 percent!, (5) I guess the ultimate test is to have multiple disjoint committees + reviewers, all with similar qualities, to evaluate the same batch of submissions, and see if they will accept similar sets of papers.

January 17, 2012

Representative image for SIGGRAPH submission

Filed under: Real — liyiwei @ 5:24 am
Tags: ,

Basically, its main function is to be displayed on the front of the room during the committee meeting, so that people can have a visual reference/cue of the paper being talked about.
Even though the representative image does not have any practical value for the paper (it is not illegal to use an arbitrary image, like, say, picture of Lindsay Lohan, at least with clothes on), the committee members are humans and thus can be subtly influenced by all psychological factors.
Thus, it is to your advantage to use an image that can help your paper, i.e. conveys the main ideas or results while looks appealing.

December 30, 2011

James Landay on “China Will Overtake the US in Computing…Maybe, Someday…”

Filed under: Real — liyiwei @ 7:47 pm
Tags: , , , , , ,

This is a mandatory reading for all my (current and future) students with an initial Asian training:

James Landay on China Will Overtake the US in Computing…Maybe, Someday…

First of all, let me share one of the biggest secrets of China (and to some degree other Asian countries like Japan and Korea as well as ethnic Chinese states like Taiwan and Singapore). Do you ever wonder why China developed this authoritarian culture in the first place? It is very simple: a conforming population is much easier to rule than one that can think freely. The Chinese emperors were very calculating on this; they did not even allow alternative sources of authorities to challenge them (like the bishops who can thorn up to European emperors’ arses). On the other hand, they also want the population to be reasonably fluent so that the country can be productive. Thus the duality of the Chinese/Asian education system: on one hand it enforces conformity, and on the other encourages intellect and hard working.
Unfortunately, even though this system worked for the past agriculture and manufacture dominant economic systems, a knowledge-based economy will require citizens who can think. So China will have to change its culture and education systems, or face competitive disadvantages.

Part of the fun for my past MSR and current HKU posts is being close enough to help while far enough to not get dragged down into the sinkhole. I am curious how much I can do as an individual, or there is really some grander scale environmental stuff that I simply cannot reproduce. Results so far are very encouraging; Asian students who worked with me for sufficiently long periods of time (at least one SIGGRAPH cycle) have shown significant progress of thinking skills and at least one of them managed to create SIGGRAPH ideas.

For the sake of more fun, I now extend my grand challenge to MSR Asia to all my (past, current, and future) students: the first one to publish a single-authored SIGGRAPH paper will receive my full financial support, out of my own pocket instead of any grant, to make the trip. (Really, it is not that hard; I am not very smart, and I did that twice already. I make this challenge because only with a single-authored SIGGRAPH paper can you prove your full independence, including creativity.)

September 17, 2011

Producing research results

Filed under: Real — liyiwei @ 4:06 pm
Tags: , , ,

Sylvain Lefebvre has a nice post about how to structure code for producing research results; see here. (Full disclosure: Sylvain is my collaborator, but he is a superb researcher and coder, as evident from his resume.)

May 16, 2011

SIGGRAH contributor discount

Filed under: Real — liyiwei @ 3:18 pm
Tags: ,

SIGGRAPH gives one contributor code to each technical paper so that at most one author can get a 50 percent registration discount. However, the discount is not accumulative, so (in effect) each author can receive at most one contributor code. By considering the fact that some authors may be on multiple papers, it becomes an interesting optimization problem on how to assign the contributor codes among all paper authors to maximize the total number of utilized discounts.

Under the general scenarios, this looks like an NP hard problem. (Correct me if I am wrong, as I am very rusty about basic algorithm theories.) By constructing a pathological scenario with the right number of total authors and authors on each paper, this can be quite a difficult problem to solve.

Fortunately, the reality is much simpler; since the number of papers for each author is usually quite limited, the *relationship graph* among all authors contain many isolated islands (that can be solved independently). In fact, I have found that a very simple randomized algorithm would just work: visit the papers in a random order, and pick a random author that has yet received any contributor code.

The results for SIGGRAPH 2011 technical papers are as follows. For each paper, blue color indicates the author receiving the contributor code, red color indicates authors who receive codes from other papers, and gray color indicates authors who receive nothing.

(I hope ACM won’t ban me from attending SIGGRAPH.)

Physically-valid Statistical Motion Models for Human Motion Synthesis
Xiaolin Wei
Jianyuan Min
Jin-Xiang Chai

Motion Capture From Body-Mounted Cameras
Takaaki Shiratori
Hyun Soo Park
Leonid Sigal
Yaser Sheikh
Jessica Hodgins

Motion Reconstruction Using Sparse Accelerometer Data
Jochen Tautges
Arno Zinke
Bjorn Kruger
Jan Baumann
Andreas Weber
Thomas Helten
Meinard Muller
Hans-Peter Seidel
Bernd Eberhardt

Video-based Characters – Creating New Human Performances from a Multi-view Video Database
Feng Xu
Yebin Liu
Carsten Stoll
James Tompkin
Gaurav Bharaj
Qionghai Dai
Hans-Peter Seidel
Jan Kautz
Christian Theobalt

ShadowDraw: Real-Time User Guidance for Freehand Drawing
Yong Jae Lee
Larry Zitnick
Michael F. Cohen

OverCoat: An Implicit Canvas for 3D Painting
Johannes Schmid
Martin Sebastian Senn
Markus Gross
Robert Sumner

A Programmable System for Artistic Volumetric Lighting
Derek Nowrouzezahrai
Jared Johnson
Andrew Selle
Dylan Lacewell
Michael Kaschalk
Wojciech Jarosz

Coherent Noise for Non-Photorealistic Rendering
Michael Kass
Davide Pesare

Exploration of Continuous Variability in Collections of 3D Shapes
Maksim Ovsjanikov
Wilmot Li
Leonidas Guibas
Niloy J. Mitra

Characterizing Structural Relationships in Scenes Using Graph Kernels
Matthew Fisher
Manolis Savva
Pat Hanrahan

Probabilistic Reasoning for Assembly-Based 3D Modeling
Siddhartha Chaudhuri
Evangelos Kalogerakis
Leonidas Guibas
Vladlen Koltun

Shape google: Geometric words and expressions for invariant shape retrieval
Alexander Bronstein
Michael Bronstein
Leonidas Guibas
Maksim Ovsjanikov

Eulerian Solid Simulation With Contact
David I.W. Levin
Joshua Litven
Garrett L. Jones
Shinjiro Sueda
Dinesh Pai

Efficient Elasticity for Character Skinning with Contact and Collisions
Aleka McAdams
Yongning Zhu
Andrew Selle
Mark Empey
Rasmus Tamstorf
Joseph M. Teran
Eftychios Sifakis

Toward High-Quality Modal Contact Sound
Changxi Zheng
Doug James

A Nonsmooth Newton Solver for Capturing Exact Coulomb Friction in Fiber Assemblies
Florence Bertails-Descoubes
Florent Cadoux
Gilles Daviet
Vincent Acary

Large-Scale Dynamic Simulation of Highly Constrained Strands
Shinjiro Sueda
Garrett L. Jones
David I.W. Levin
Dinesh Pai

HDR-VDP-2: A calibrated visual metric for visibility and quality predictions in all luminance conditions
Rafal Mantiuk
Kil Joong Kim
Allan G. Rempel
Wolfgang Heidrich

A Versatile HDR Video Production System
Mike Tocci
Chris Kiser
Nora Tocci
Pradeep Sen

Perceptually Based Tone Mapping for Low-Light Conditions
Adam G. Kirk
James F. O’Brien

Illumination Decomposition for Material Recoloring with Consistent Interreflections
Rob Carroll
Ravi Ramamoorthi
Maneesh Agrawala

High-Quality Spatio-Temporal Rendering using Semi-Analytical Visibility
Carl Johan Gribel
Rasmus Barringer
Tomas Akenine-Moller

Frequency Analysis and Sheared Filtering for Shadow Light Fields of Complex Occluders
Kevin Egan
Florian Hecht
Fredo Durand
Ravi Ramamoorthi

Temporal Light Field Reconstruction for Rendering Distribution Effects
Jaakko Lehtinen
Timo Aila
Jiawen Chen
Samuli Laine
Fredo Durand

The Area Perspective Transform: A Homogeneous Transform for Efficient In-Volume Queries
Warren Hunt
Greg Johnson

Building Volumetric Appearance Models of Fabric using Micro CT Imaging
Shuang Zhao
Wenzel Jakob
Steve Marschner
Kavita Bala

Pocket Reflectometry
Peiran Ren
Jiaping Wang
John Snyder
Xin Tong
Baining Guo

Microgeometry Capture Using an Elastomeric Sensor
Micah Johnson
Forrester Cole
Alvin Raj
Edward Adelson

CATRA: Interactive Measuring and Modeling of Cataracts
Vitor F. Pamplona
Erick Baptista Passos
J Zizka
Manuel M. Oliveira
Esteban Clua
Ramesh Raskar

Blue-Noise Point Sampling using Kernel Density Model
Raanan Fattal

Efficient Maximal Poisson-Disk Sampling
Mohamed S. Ebeida
Anjul Patney
Scott A. Mitchell
Andrew Davidson
Patrick M. Knupp
John D. Owens

Differential Domain Analysis for Non-uniform Sampling
Li-Yi Wei
Rui Wang

Filtering Solid Gabor Noise
Ares Lagae
George Drettakis

GlobFit: Consistently Fitting Primitives by Discovering Global Relations
Yangyan Li
Xiaokun Wu
Yiorgos Chrysanthou
Andrei Sharf
Daniel Cohen-Or
Niloy J. Mitra

Global Registration of Dynamic Range Scans for Articulated Model Reconstruction
Will Chang
Matthias Zwicker

Texture-Lobes for Tree Modelling
Yotam Livny
Soeren Pirk
Zhanglin Cheng
Feilong Yan
Oliver Deussen
Daniel Cohen-Or
Baoquan Chen

L1-sparse Reconstruction of Sharp Point Set Surfaces
Haim Avron
Andrei Sharf
Chen Greif
Daniel Cohen-Or

Interactive and Anisotropic Geometry Processing Using the Screened Poisson Equation
Ming Chuang
Michael Kazhdan

Dinus: Double insertion, nonuniform, stationary subdivision surfaces
Kerstin Muller
Christoph Funfzig
Lars Reusche
Dianne Hansford
Gerald Farin
Hans Hagen

An Efficient Scheme for Curve and Surface Construction Based on a Set of Interpolatory Basis Functions
Ren-Jiang Zhang
Weiyin Ma

A Quantized-Diffusion Model for Rendering Translucent Materials
Eugene d’Eon
Geoffrey Irving

A Comprehensive Theory of Volumetric Radiance Estimation using Photon Points and Beams
Wojciech Jarosz
Derek Nowrouzezahrai
Iman Sadeghi
Henrik Wann Jensen

Progressive Photon Mapping: A Probabilistic Approach
Claude Knaus
Matthias Zwicker

Cache-Oblivious Ray Reordering
Bochang Moon
Youngyong Byun
Tae-Joon Kim
Pio Claudio
Hye-sun Kim
Yun-ji Ban
Seung Woo Nam
Sung-Eui Yoon

Expression Flow for 3D-Aware Face Component Transfer
Fei Yang
Jue Wang
Eli Shechtman
Lubomir Bourdev
Dimitris Metaxas

Image-Guided Weathering: A New Approach Applied to Flow Phenomena
Carles Bosch
Pierre-Yves Laffont
Holly Rushmeier
Julie Dorsey
George Drettakis

Exploring Photobios
Ira Kemelmacher-Shlizerman
Rahul Garg
Steven M. Seitz
Eli Shechtman

Discrete Element Textures
Chongyang Ma
Li-Yi Wei
Xin Tong

Space-time Planning with Parameterized Locomotion Controllers
Sergey Levine
Yongjoon Lee
Vladlen Koltun
Zoran Popovic

Articulated Swimming Creatures
Jie Tan
Yuting Gu
Greg Turk
C. Karen Liu

Locomotion Skills for Simulated Quadrupeds
Stelian Coros
Andrej Karpathy
Ben Jones
Lionel Reveret
Michiel van de Panne

Composite Control of Physically Simulated Characters
Uldarico Muico

Character Animation in Two-player Adversarial Games
Kevin Wampler
Erik Andersen
Evan Herbst
Yongjoon Lee
Zoran Popovic

Color Compatibility from Large Datasets
Peter O’Donovan
Aseem Agarwala
Aaron Hertzmann

Edge-Aware Color Appearance
Min H. Kim
Tobias Ritschel
Jan Kautz

Example-based Image Color and Tone Style Enhancement
Baoyuan Wang
Yizhou Yu
Ying-Qing Xu

Switchable Primaries Using Shiftable Layers of Color Filter Arrays
Behzad Sajadi
Aditi Majumder
Kazuhiro Hiwada
Ramesh Raskar

Contributing Vertices-Based Minkowski Sum of a Non-Convex–Convex Pair of Polyhedra
Hichem Barki
Florence Denis
Florent Dupont

MeshFlow: Interactive Visualization of Mesh Construction Sequences
Jonathan Denning
William Kerr
Fabio Pellacini

LR: Compact Connectivity Representation for Triangle Meshes
Topraj Gurung
Mark Luffel
Peter Lindstrom
Jarek Rossignac

On the Velocity of an Implicit Surface
Jos Stam
Ryan Schmidt

Data-Driven Elastic Models for Cloth: Modeling and Measurement
Huamin Wang
James F. O’Brien
Ravi Ramamoorthi

Frame-based Elastic Models
Benjamin Gilles
Guillaume Bousquet
Francois Faure
Dinesh Pai

Example-Based Elastic Materials
Sebastian Martin
Bernhard Thomaszewski
Eitan Grinspun
Markus Gross

Sparse Meshless Models of Complex Deformable Objects
Francois Faure
Benjamin Gilles
Guillaume Bousquet
Dinesh Pai

Antialiasing Recovery
Lei Yang
Pedro V. Sander
Jason Lawrence
Hugues Hoppe

Local Laplacian Filters: Edge-aware Image Processing with a Laplacian Pyramid
Sylvain Paris
Samuel W. Hasinoff
Jan Kautz

Domain Transform for Edge-Aware Image and Video Processing
Eduardo S. L. Gastal
Manuel M. Oliveira

Non-Rigid Dense Correspondence with Applications for Image Enhancement
Yoav Hacohen
Eli Shechtman
Dan Goldman
Dani Lischinski

Leveraging Motion Capture and 3D Scanning for High-Fidelity Facial Performance Acquisition
Haoda Huang
Jin-Xiang Chai
Xin Tong
Hsiang-Tao Wu

High-Quality Passive Facial Performance Capture Using Anchor Frames
Thabo Beeler
Fabian Hahn
Derek Bradley
Bernd Bickel
Paul Beardsley
Craig Gotsman
Bob Sumner
Markus Gross

Interactive Region-based Linear 3D Face Models
Jose Rafael Tena
Fernando de la Torre
Iain Matthews

Realtime Performance-Based Facial Animation
Thibaut Weise
Sofien Bouaziz
Hao Li
Mark Pauly

Bounded Biharmonic Weights for Real-Time Deformation
Alec Jacobson
Ilya Baran
Jovan Popovic
Olga Sorkine

Blended Intrinsic Maps
Vladimir G. Kim
Yaron Lipman
Thomas Funkhouser

Biharmonic Distance
Yaron Lipman
Raif Rustamov
Thomas Funkhouser

Photo-Inspired Model-Driven 3D Object Modeling
Kai Xu
Hanlin Zheng
Hao Zhang
Daniel Cohen-Or
Ligang Liu
Yueshan Xiong

Two-Scale Particle Simulation
Barbara Solenthaler
Markus Gross

Real-Time Eulerian Water Simulation Using a Restricted Tall Cell Grid
Nuttapong Chentanez
Matthias Mueller

A PML-Based Nonreflective Boundary for Free Surface Fluid Animation
Andreas Soderstrom
Matts Karlsson
Ken Museth

Guide shapes for high resolution naturalistic liquid simulation
Michael Nielsen
Robert Bridson

Animating Fire With Sound
Jeffrey Chadwick
Doug James

Converting 3D Furniture Models to Fabricatable Parts and Connectors
Manfred Lau
Akira Ohgawara
Jun Mitani
Takeo Igarashi

Make it Home: Automatic Optimization of Furniture Arrangement
Lap-Fai Yu
Sai-Kit Yeung
Chi-Keung Tang
Demetri Terzopoulos
Tony F. Chan
Stanley Osher

Interactive Furniture Layout Using Interior Design Guidelines
Paul Merrell
Eric Schkufza
Zeyang Li
Maneesh Agrawala
Vladlen Koltun

Interactive Architectural Modeling with Procedural Extrusions
Tom Kelly
Peter Wonka

Metropolis Procedural Modeling
Jerry O. Talton
Yu Lou
Steve Lesser
Jared Duke
Radomir Mech
Vladlen Koltun

Sensitive Couture for Interactive Garment Design
Nobuyuki Umetani
Danny Kaufman
Takeo Igarashi
Eitan Grinspun

Real-Time Large-Deformation Substructuring
Jernej Barbic
Yili Zhao

Solid Simulation with Oriented Particles
Matthias Mueller
Nuttapong Chentanez

Physics-Inspired Upsampling for Cloth Simulation in Games
Ladislav Kavan
Daniel Gerszewski
Adam Bargteil
Peter-Pike Sloan

Image and Video Upscaling from Local Self-Examples
Gilad Freeman
Raanan Fattal

Scalable and Coherent Video Resizing with Per-Frame Optimization
Yu-Shuen Wang
Jen-Hung Hsiao
Olga Sorkine
Tong-Yee Lee

Subspace Video Stabilization
Feng Liu
Michael Gleicher
Jue Wang
Hailin Jin
Aseem Agarwala

Tonal Stabilization of Video
Zeev Farbman
Dani Lischinski

Making Burr Puzzles from 3D Models
Shi-Qing Xin
Chi-Fu Lai
Chi-Wing Fu
Tien-Tsin Wong
Ying He
Daniel Cohen-Or

A Geometric Study of V-style Pop-ups: Theories and Algorithms
Xian-Ying Li
Tao Ju
Yan Gu
Shi-Min Hu

Depixelizing Pixel Art
Johannes Kopf
Dani Lischinski

Digital Micrography
Ron Maharik
Mikhail Bessmeltsev
Alla Sheffer
Ariel Shamir
Nathan Carr

Computational Stereo Camera System With Programmable Control Loop
Simon Heinzle
Pierre Greisen
David Gallup
Christine Chen
Daniel Saner
Aljoscha Smolic
Andreas Peter Burg
Wojciech Matusik
Markus Gross

Highlighted DOF Photography: Shining Light on Focus
Jaewon Kim
Roarke Horstmeyer
Ig-Jae Kim
Ramesh Raskar

Layered 3D: Tomographic Image Synthesis for Attenuation-based Light Field and High Dynamic Range Displays
Gordon Wetzstein
Douglas Lanman
Wolfgang Heidrich
Ramesh Raskar

A Perceptual Model for Disparity
Piotr Didyk
Tobias Ritschel
Elmar Eisemann
Karol Myszkowski
Hans-Peter Seidel

Circular arc structures
Pengbo Bo
Helmut Pottmann
Martin Kilian
Wenping Wang
Johannes Wallner

Discrete Laplacians on General Polygonal Meshes
Marc Alexa
Max Wardetzky

HOT: Hodge-Optimized Triangulations
Patrick Mullen
Pooran Memari
Fernando de Goes
Mathieu Desbrun

Spin Transformations of Discrete Surfaces
Keenan Crane
Ulrich Pinkall
Peter Schroder

Interactive Editing of Massive Imagery Made Simple: Turning Atlanta into Atlantis
Brian Summa
Giorgio Scorzelli
Ming Jiang
Peer-Timo Bremer
Valerio Pascucci

Geodesic Image and Video Editing
Antonio Criminisi
Toby Sharp
Carsten Rother
Patrick Perez

Matting and Compositing of Transparent and Refractive Objects
Sai-Kit Yeung
Chi-Keung Tang
Michael S. Brown
Sing Bing Kang

Nonlinear Revision Control for Images
Hsiang-Ting Chen
Li-Yi Wei
Chun-Fa Chang

Clipless Dual-Space Bounds for Faster Stochastic Rasterization
Samuli Laine
Timo Aila
Tero Karras
Jaakko Lehtinen

Decoupled Sampling for Graphics Pipelines
Jonathan Ragan-Kelley
Jaakko Lehtinen
Jiawen Chen
Michael Doggett
Fredo Durand

Spark: Modular, Composable Shaders for Graphics Hardware
Tim Foley
Pat Hanrahan

Physically Based Real-Time Lens Flare Rendering
Matthias Hullin
Elmar Eisemann
Hans-Peter Seidel
Sungkil Lee

December 20, 2010

How to use the papers committee list

Filed under: Real — liyiwei @ 11:49 am
Tags: , , ,

SIGGRAPH now publishes the technical papers committee list a few weeks prior to the submission deadline. Here is my suggestion on how to take this information to your advantage.

First, let me tell you what NOT to do. It is very common for people to try to guess who is likely to review your papers, but this is entirely useless and counterproductive. In general, there is indeed a positive correlation between the committee member expertise and your paper subject, but it is not a very strong correlation and there is a non-trivial chance that a paper will be assigned to an unexpected committee member. (This is mainly due to how the paper sorting and assignment process goes but I am not going to elaborate on this here because I do not think it is necessary for authoring a good paper.)

So my personal strategy is to make sure the paper will survive *any* committee member. This is the safest bet and you cannot go wrong with that. (But do check the committee member list constantly though as sometimes it may change prior to the deadline.) Specifically, you should write your paper (especially the title and abstract) in a way so that it is as clear as possible on what it is all about to minimize the chance of misunderstanding. (If the paper sorters misunderstand your paper, they are more likely to assign your paper to the wrong committee member. And if the senior reviewers misunderstand your paper, they are more likely to assign your paper to the wrong tertiaries. And if reviewers misunderstand your paper they are more likely to score it lowly.)

It also helps to read and cite papers from the committee members for two reasons. The first reason is that the background and expertise of a committee member will obviously have a huge influence on how she is going to review a paper, so if you understand her, you stand a better chance of appreciating how she might approach a paper. The second reason is that psychological studies indicate that it is almost never too much to flatter, and people are usually happy to see their own papers cited and attributed in a positive manner.

If you want to push this further, my personal philosophy is to assume that my paper will be reviewed by the worst possible reviewers and prepare for that. Like Andy Grove said, only the paranoid survive.

August 7, 2010

Social pass

Filed under: Real — liyiwei @ 10:15 am
Tags: , ,

It will be great if SIGGRAPH (and other conferences) could have a new registration category called “social pass”. This social pass will be (significantly) cheaper than full registration, and is designed primarily for people who go to conferences mainly to socialize with colleagues. When I was in grad school I used to listen attentively to all the technical sessions, but nowadays (for better or worse) I found myself spending so much time chatting with people to the point that I serious doubt the value I paid for a full registration. I still go to many technical sessions, but my main purpose now turn to meet specific people (e.g. paper authors or people who work on related fields) and pay enough attention to the presentations so that I could have enough information to chat up with the authors later on. (Man, I like your presentation, especially demo XXX. What a cool paper!)

On a further thought, I could be tricky to design such a social pass. If I just want to talk to people in the hallways, I actually do not have to pay a dime and just need to walk into the convention center. But then that might not be enough, as a lot of the conversations happen inside the sessions (especially at the beginnings and ends) and the parties (most of which, hosted by various companies and research groups, I could already go for free). So I still need the credential to attend a certain subset of full registration.

Maybe one possibility is to charge for individual sessions so that I could pick only these that I plan to attend (to socialize). For the rest, I could simply loiter in the hallways and the parties.

April 12, 2010

Accidental art

Filed under: Imaginary,Real — liyiwei @ 2:55 pm
Tags: , , ,

For some reason, the most beautiful images I have produced tend to be the buggy ones.

I guess this is a unique advantage of graphics research (compared to other CS fields): when we screw up, we might be able to claim the result as an art.

March 3, 2010

How to do rebuttal

Filed under: Real — liyiwei @ 6:21 pm
Tags: , ,

(This is mainly for SIGGRAPH, but can be adapted to other scenarios.)

Check out Aaron Hertzmann’s blog about rebuttal as well. In short, our goal of the rebuttal is to convince the reviewers to accept the paper, regardless of the official rules.

First of all, understand the rebuttal process by reading the relevant information, e.g. the email from paper chair as well as the SIGGRAPH website. These already provide useful hints. Below are my additional suggestions.

The basics
Rebuttal is a scripted process, and it is not about the scores. The content does depend on the reviews, but the process should remain the same if you are rational.

Rebuttal does make a difference, not always, but frequent enough to worth the efforts. I have had a paper accepted with average score $<$ 2.8, and a paper rejected with average score $>$ 4.0 (out of a 5.0 scale).

The psychology
It is human nature to rate their own works more highly than others would. So you will likely get disappointed, especially for venues with high quality bar like SIGGRAPH. Lowering your expectation can help. (I usually assume the worst case scenario.) As you become more experienced you might be able to stand in the reviewers shoes and judge your own work more objectively with less emotional attachment. But before that, I suggest following a pre-scripted procedure.

Feel free to design your own procedure that works best for you, but here is mine for your reference. I designed it in a way so that in no stage would your emotion be easily slipped in.

. Save the review files somewhere (svn check-in the plain text .htm files if you are collaborating with me).

. Read the reviews once, grouped by reviewers instead of questions. This will give you a more coherent impression of each reviewer’s general stance. It also allows you a chance to vent (in a non-harmful way); if you feel angry now, go punch the wall or something. Do not proceed to the following stages until you are sufficiently relieved.

. Prepare a blank document for the rebuttal text. If you are collaborating with me via svn, check in the document first.

. Read the reviews again, and write down the questions in the rebuttal document that remotely seem to need answering. (Yes, we should keep the rebuttal document reasonably short and try not to answer every single question, but we need to identify the important ones first. This is why I prefer to be more conservative in listing questions in this early stage.) Focus on the questions now and do not worry about answers in this stage.

. It is likely that different reviewers might ask the same or similar questions. If so, consolidate the questions and mark the corresponding reviewer ids.

. Sort the questions in a roughly prioritized order, put in front these questions that are more important (e.g. factual misunderstanding/misinterpretation or specific questions asked by reviewers that they wish you to address in the rebuttal). Do not remove any question at this stage.

. Start adding answers to the questions. In the process, we might need to reorganize the questions and their orders. This is a natural process of writing rebuttal, just like writing the paper. We will iterate multiple rounds until every co-author is satisfied with the document.

. The official suggestion is to keep the rebuttal document short, but I would prefer to make it longer than necessary instead of risking omit important questions. (It is not always easy to correctly identify which questions are really important.) Of course the rebuttal text cannot run over the size limit (e.g. 2000 words), but to avoid confusing the reviewers, I usually separate the rebuttal into two parts: the main part for major and common questions, and the detailed part for individual reviewers. My personal experience as a reviewer (both primary/secondary and tertiary) is that I would not mind seeing a rebuttal running up to the length as long as the main part is clearly marked and shown up front. This allows me the flexibility to skip the more detailed parts if necessary. I have also observed that the reviewers tend to feel respected if the authors answer their questions, even for relatively minor ones.

. Before sending out the rebuttal text, add a short paragraph in the very beginning to thank all the reviewers for their effort in reading your paper and all the wonderful comments they have made.

. Submit the rebuttal. Do it early instead of waiting for the last minute, for obvious reasons. If the mechanism allows you to overwrite the previous uploads, definitely do so early. You can update the document later.

January 12, 2010

How to deal with paper deadlines

Filed under: Real — liyiwei @ 1:57 pm
Tags: , ,

(Below is what I sent out to my collaborators for SIGGRAPH. I believe similar principles could be applied for other conferences as well.)

1. I recommend that only one person (the account creator) uploads materials to the sis account during the last day prior to the deadline, to avoid confusion and potential concurrent read/write hazards. I am usually a bad choice for material uploads as I will become a sequential bottleneck for uploading to multiple accounts. (Not to mention that I might get confused and mixed up the materials.) The same person should also be responsible to check all fields of the submission account to make sure everything is correct. I would usually take a pass to check everything, but the buck has to stop with the account creator.

2. The SIS server would usually be overloaded during the last few hours prior to the deadline, so upload all materials early and frequently. You can always overwrite the old materials with the new ones. If you wait until the last few hours or even minutes and find out that you cannot access the server, do not cry for help from me. I do not control the servers and there is nothing I can do.

3. On a similar vein, even though it is possible to upload only the checksums for the files prior to the deadline and upload materials with identical checksums later, I strongly recommend against doing so, unless you are very sure what you are doing. The main reason is that even with the same source files, different compilations could produce binary data with different checksums, e.g. pdflatex. So if you accidentally overwrite or lose the file, you are screwed. My overall recommendation is to avoid uploading anything in the last 2 to 3 hours prior to the deadline; this not only avoids potential server overloads but also help ensure that the files you uploaded are “sane”, for which humans tend not to be near the deadline according to my experience.

4. (For my collaborators in particular)
Do not assume I will be available during the last 8 hours prior to the deadline. Humans tend to procrastinate and end up with a lot of work for the last minutes. (I see this every single year, and I *never* understand why.) Unfortunately, given the number of projects I am usually involved with, it is mathematically impossible for me to spend the kind of time (every one of) you would prefer during these rush hours. So to lower people’s expectation and to encourage better time management, simply assume I will not be responding.

July 31, 2009

Beignets in Cafe Du Monde

Filed under: Real — liyiwei @ 4:30 pm
Tags: , ,

I had these for breakfast in an extremely hot and humid morning in New Orleans.

Beignets in Cafe Du Monde

July 6, 2009

Speech synthesizer

Filed under: Real — liyiwei @ 6:31 pm
Tags: , ,

If you find yourself right in front of a SIGGRAPH deadline, and have problem finding someone to dub the video for you, and you do not want to do it yourself to avoid exposing your identity, then this free speech synthesizer from AT&T might save your day.

I tested it with my prior SIGGRAPH video scripts; the narration could sound like borg occasionally, but in general good enough so that I would pick the synthesized voice instead of mine.

Maybe the act of having someone to dub the video will soon become a SIGGRAPH legacy, among calibrating printers for optimal image quality and sending someone on a trip for physical delivery.

April 21, 2009

Similar image search

Filed under: Real — liyiwei @ 11:19 am
Tags: , , , , ,

Google’s new toy similar image search looks intriguing, but still it does not allow query by images directly.

True content-based image search is definitely very hard, and so far I haven’t seen any system that (remotely) works.

I do not know exactly how Google’s similar image search is implemented, but it could entirely avoid content-based image search by providing similarity links between images that are already indexed in Google’s database. Thus, the similarity computation could not only be conducted offline, but also leverage contextual information such as texts surrounding images. The similarity links could even be edited by humans if necessary.

I still remember the first encounter that prompted me to feel the need for content-based image search. After submitting my camera-ready paper to SIGGRAPH 2000, Stephen Spencer asked me to secure proper copyrights for all images used in the paper. But there is this famous little green texture that I simply could not track down the original ownership (even until today).

If there is a system that would allow me to do so, I will consider it a real success. (I am looking forward to Google’s official deployment of their similar image search system to see if I could unveil the true origin of “my little green friend”).

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