Older blog entries for walken (starting at number 14)

Damn ! I havent posted here for one month.

Lots of stuff have happened in the libmpeg2 since last time. I checked in the work I did on the slice decoder, basically a big restructuration of the code. Then I corrected lots of small details to make them actually comply with the standard. Then I rewrote the parsing code and we gained about 20% in decoding speed. And then MPEG1 support went in. Yummy :-)

I declared myself a lead developper. Advogato is good for your ego :-D

The next big milestones for the LiViD project will be to switch to a new API between the codecs and the output layers, and then to work on the synchronisation mechanisms. These times it seems that more people are coming to the project and trying to help. That's good. I'm trying to send detailed proposals for the output layers work, but this kind of coordination work always takes more time that you would want. It seems to be worth it though.

On the libmpeg2 side of the project, the next steps will be to implement field pictures and then the missing MC modes. The output layer work has a higher priority though, so I guess in the next days I'll not be progressing very fast on libmpeg2 proper.

Finally found a house to rent in oakland. Yay :) also opened my bank account, blablabla. Next thing is to buy a car, which also requires getting a californian license and an insurance. I'm sure I will love all this paperwork.

The NT on my new computer is half-dead already. It almost works, but for some reason it behaves like if I had some control key stuck, or I pressed the wrong mouse buttons, or I dont know what - I dont use NT much, so I dont know how you could make it not work like that. It just behaves in a very stupid way - when I click on an icon it gives me a popup menu instead of selecting it, etc... very unuseable. I have no idea when and why it started to act this way. Oh well, its only at work, so I will just have to call someone and watch him getting mad. I guess that could be fun.

It worked friday and monday, heh, two days, its not so bad for NT :-)

On the mpeg2dec side : the IDCT scaling thing is checked in, the slice rewrite is done, submitted, but not checked in yet, and I think we've made great progress since the OLS. Soon we should be able to try the mpeg compliance test bitstreams. Yummy ! :) I have not progressed any bit on the synchro stuff though.

Trying to find a cool room (with roomate) in the SF / oakland / berkeley / alameda area. Hasnt had much success yet. I have to leave my temporary appartment this weekend, so I guess I will have to spend a few days at the hotel. Oh well.

My rewrite of the mpeg2dec slice.c code seems to get into shape. I'm very happy at the look it has now - much more straightforward than any other mpeg code I have seen. I'm proud :) I will check this in sometime soon, perhaps this weekend if I'm not moving at that time.

Used my CVS write access for the first time. Yay :) That was not too big of a patch, basically a rewrite of the headers parsing functions using hand-parsing instead of the bitstream functions, and a removal of all the stuff we were parsing but never using for decoding. I think it makes things a little simpler to follow. I will have to do some changes in slice.c too, but I have carefully avoided that for now :)

Stuff to work on :

* get rid of the infamous IDCT scaling

* rewrite a lot of the slice.c code, right now we first parse everything and then run the MC/IDCT code, and a lot of the tests are duplicated between the parse side and the MC/IDCT side. I think the code will be easier to follow after I change this.

* synchro stuff, but I think there will be a lot of bitching between aaron and me on this one. It will not be a huge chunk of code but it is not easy to get right.

Back from OLS. That was great ! The confs were interesting, but of course the main discussions were between them and at the parties every evening... :)

Also I finally met aaron, which was probably half of the reason why I went there in the first place. I may get CVS access to the mpeg2dec tree soon, which should help a lot. We still dont quite understand each others views on the synchro stuff though, so I guess we will have to try things and compare code instead of ideas. We will get there eventually.

I still dont have my PIII at work, and development on this ppro 200 is a bit painfull. I still get a full 6 fps decoding rate though :->

Heading to OLS. I wish I would be there already. Oh wait, there would be nothing to do yet. I wish it would be tomorrow then :)

My slice.c /getvlc.c rewrite is progressing, but slowly. I'm trying to shorten the common pathes, with some success I think. It does break a few abstractions (like putting huffman parsing in separate routines), but it is still kind of clean. This portion of the mpeg standard is quite convoluted though, and it is not always easy to factor things out in a nice way. Lots of work to do in there, we'll see what happens :)

I also fixed a few non-conformance points (which added back some of the complexity, grumph) and potential buffer overflows...

I still dont have my P3 computer, so I'm using a ppro 200 for coding. I get about 6 fps when I'm lucky. yay :)

Moved to SF. At the airport it was a big mess because being less than 25 I could not rent a car. duh. Then I figured out I had no office and they didnt have the keys for my appartment either. Its all fixed now though :)

Still a bit tired, but heh...

Lesson of the day : my (apparently ex-) girlfriend is a lunatic. Back to our usual scheduled program...

:-/

made a bitstream patch for mpeg2dec. Its quite small, its faster than aaron's version, and I think its cleaner too. I hope it makes it into the tree soon.

My scheduler diff is not into the tree yet, I hope aaron gets some time to merge it sometime soon.

yesterday I made an ass out of myself by posting tons of messages to the livid list. Well not really an ass, but I dont like to post that much, and mostly I was nitpicking on minor issues that dont need immediate attention anyway. Heh, thats how it goes some days :)

I need to go out a bit or I will get crazy. I'm gonna move to the SF bay one week from now, and its so wierd to be here waiting for the move.

Back from weekend. On friday I'll be leaving for a 10 days holiday so I'd better not get late at work, and I have *lots* of stuff to do. I want to find the time to do the last 10% of my a/v scheduler patch, too... huh :-/

Aaron is quite busy at work too, he hasnt commented on my patches yet, so I'm on my own here. From early discussions I think we're on the same track, but I can only hope.