Converting Divx-AVI to MP4 - Output size option doesn't work

[tomzero]

Hello,

I try to convert a file with screen size 720x304 from AVI (divx) to MP4. I set the Output size in the right side of the Video options tab to 720x304, the ratio to 2.35:1, and the framerate to 25 (PAL).

I use the MPEG4[.MP4] (ffmpegx) encoder. The conversion works fine unless the output size is always 533x400.

What am I doing wrong?

Thanks in advance,
Tom

Log:

FFmpeg version CVS, Copyright (c) 2000-2004 Fabrice Bellard
Sat Aug 1 16:13:04 CEST 2009
Mac OSX universal build for ffmpegX
libavutil version: 49.0.0
libavcodec version: 51.9.0
libavformat version: 50.4.0
Input #0, avi, from '/Users/user/Movies/movie.avi':
Duration: 01:28:59.1, start: 0.000000, bitrate: 1107 kb/s
Stream #0.0, 25.00 fps(r): Video: mpeg4, yuv420p, 720x304
Stream #0.1: Audio: mp2, 48000 Hz, stereo, 128 kb/s
Output #0, mp4, to '/Users/user/Movies/movie.avi.ff.mp4':
Stream #0.0, 25.00 fps(c): Video: mpeg4, yuv420p, 720x304, q=2-9, 1617 kb/s
Stream #0.1: Audio: aac, 48000 Hz, stereo, 96 kb/s
Stream mapping:
Stream #0.0 -> #0.0
Stream #0.1 -> #0.1
bench: utime=784.024s
video:1053425kB audio:62560kB global headers:0kB muxing overhead 0.279503%
Encoding completed on Sat Aug 1 16:25:20 CEST 2009

[dizzie]

I don't get the error when I try it. What is your input source? A VIDEO_TS folder? If so, you may give Handbrake a try.

[Case]

I can replicate this issue. The output resolution is 720x304 as specified (as MediaInfo Mac will confirm), but some display aspect ratio flag isn't set properly, so that the player software stretches the video to a 4:3 aspect ratio.

If I remember correctly, this will happen for every conversion to .mp4 using this engine, when the target isn't exactly 16:9 or 4:3. So for 2.35:1 output, this problem comes up, unfortunately.
It could be that the ffmpeg team has fixed this already, but ffmpegX has to be updated to work with that. I'm not holding my breath...

You can change the display aspect ratio in QuickTime Pro, but you'll end up with a .mov container.
What is really needed here, is an MP4 toolbox to change (correct) just the display aspect ratio, without altering the rest of the file. Anyone know of such a piece of software?

[tomzero]

Hi Case,

thanks for the analysis. Importing the file into iTunes did the job.

Best regards,
Tom

[dizzie]

I can replicate this issue. The output resolution is 720x304 as specified (as MediaInfo Mac will confirm), but some display aspect ratio flag isn't set properly, so that the player software stretches the video to a 4:3 aspect ratio.

If I remember correctly, this will happen for every conversion to .mp4 using this engine, when the target isn't exactly 16:9 or 4:3. So for 2.35:1 output, this problem comes up, unfortunately.
It could be that the ffmpeg team has fixed this already, but ffmpegX has to be updated to work with that. I'm not holding my breath...

You can change the display aspect ratio in QuickTime Pro, but you'll end up with a .mov container.
What is really needed here, is an MP4 toolbox to change (correct) just the display aspect ratio, without altering the rest of the file. Anyone know of such a piece of software?

Case, when are you going to take over development of ffmpegx????

[Case]

Case, when are you going to take over development of ffmpegx?

Hehe, I haven't programmed software in a very long time, and never on Mac OS. It would take a lot of research before I even can write a first line of code. Not worth the effort, as long as some current software does what I need. Besides, major has never hinted at handing over any source code to anyone.
Thanks for the vote of confidence, though.

[Case]

What is really needed here, is an MP4 toolbox to change (correct) just the display aspect ratio, without altering the rest of the file.

MP4Box can do this by setting the pixel aspect ratio to 1:1.
http://forum.videohelp.com/threads/3...=1#post1970798