FunMan
19th January 2003, 20:50
I know that XviD Development Tree is, as word said, "in development" and that this could negatively impact in ISO MPEG-4 conformity. But I think that it's important to report this bug. I'm using Xvid development tree from long time. Remember that I use Xvid as ISO MPEG-4 codec in mp4 file format, played with Envivio TV. Today I notice a strange thing so I had done several tests in order to understand where is the problem. The "strange thing" is the impossibility to forward and backward in the movie, and the video/audio sync problem forcing this operation. Considering tests I made I think the problem is Qpel.
I used my personal compiled version of XviD from CVS (compiled with VC7) but also using Koepi build 15012003 I've the same problem. I don't remeber any problem with previous version, in particolar with Koepi 03012003, but in this case the Xvid codec had a bug in iframe managment. So the question is: is it possible that working on Qpel code (Qpel has been modified, ins't it?) from 03/01 to 15/01 the codec has loss ISO MPEG-4 interoperability using this feature (Qpel)?
If anyone wants to test the problem my advice is to simply create an mp4 (using mp4ui from www.mediacruiser.de/mp4UI/ or using MPEG4IP from www.mpeg4ip.net) from XviD avi (obviously using the last dev tree Xvid binary with settings reported below) and to play it with Envivio TV player (www.envivio.com)
These are my XviD settings:
Motion search precision: Ultra High
Quantization type: H.263
FourCC used: DX50 (using bframe mp4ui automatically removes the delay if recognize the avi as DivX+bframes)
Maximum iframe interval: 300
Minimun iframe interval: 1
Croma motion enabled
Quarter pel enabled
Bframe enabled (5/100/100)
DivX5 B-VOP compatibility enabled
Costant quant 2
Thanks,
FunMan
I used my personal compiled version of XviD from CVS (compiled with VC7) but also using Koepi build 15012003 I've the same problem. I don't remeber any problem with previous version, in particolar with Koepi 03012003, but in this case the Xvid codec had a bug in iframe managment. So the question is: is it possible that working on Qpel code (Qpel has been modified, ins't it?) from 03/01 to 15/01 the codec has loss ISO MPEG-4 interoperability using this feature (Qpel)?
If anyone wants to test the problem my advice is to simply create an mp4 (using mp4ui from www.mediacruiser.de/mp4UI/ or using MPEG4IP from www.mpeg4ip.net) from XviD avi (obviously using the last dev tree Xvid binary with settings reported below) and to play it with Envivio TV player (www.envivio.com)
These are my XviD settings:
Motion search precision: Ultra High
Quantization type: H.263
FourCC used: DX50 (using bframe mp4ui automatically removes the delay if recognize the avi as DivX+bframes)
Maximum iframe interval: 300
Minimun iframe interval: 1
Croma motion enabled
Quarter pel enabled
Bframe enabled (5/100/100)
DivX5 B-VOP compatibility enabled
Costant quant 2
Thanks,
FunMan