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Divx converte and ffmpeg3/10/2024 ![]() You may need to add -target pal-dvd to the above command to force a certain buffer size. For example: ffmpeg -i "in.wmv" -f lavfi -i aevalsrc=0 -shortest -c:v mpeg2video -qscale:v 2 -c:a libmp3lame "out.mpg" ![]() Use -f lavfi -i aevalsrc=0 to generate a silent audio stream. Messing with the number of B-frames, motion estimation method or GOP size may tweak the quality a little but won't result in big changes. If you don't care for the bitrate start with 2 and see if that works for you. The number here ranges from 1 to 31 and higher means lower quality. MPEG-2 is really not very compression-efficient and works better at higher bitrates. Remember that DVDs use MPEG-2 and come in about 4.7 GB for 2hrs of movie, so you end up with around 5–8 MBit/s. For example, use -b:v 6000k -target pal-dvd.įor 720p, I think that you should still use a higher bitrate. You need at least double that or even more to make the result look good. If it's HD video, you will not get far with only 2.5 MBit/s. You have a few options if you want to stick with MPEG-2: MPEG-2 is also not the best choice as a codec these days. The problem is that the default bitrate for the MPEG-2 is rather low (as with most other video encoders in ffmpeg, the H.264 one being an exception). I am using a Zeranoe FFMPEG build on Windows 7. (in.mpg are the files produced by the same FFMPEG binary and the same source WMV file using the first two commands in the question). ![]() Gives "buffer underflow" and "packet too large" errors. I have generated a same-length (second-precise) silence OGG Vorbis file using Audacity but I can't manage to merge it with the video: ffmpeg -i in.mpg -i silence.ogg -c:v copy -c:a libmp3lame out.mpgĪnd even bare ffmpeg -i in.mpg -c:v copy -out.mpg What parameters do I have to use to save as much quality as possible? Compression ratio doesn't matter at all, even increase in file size is acceptable.Īnther thing I actually need (I have chosen not to include it in the question title to avoid making it too specific but I'd appreciate it being considered in the answers) is adding pure silence as a sound track - there is no sound in the original but the TV set complains about it and I'd like to get rid of this complain. (I have found this somewhere in the Internet and modified a little bit - changed the resoultion, the refresh rate and the output format (from VOB to bare MPG)) succesfully but the quality is still too bad. I have also tried ffmpeg -i "in.wmv" -c:v mpeg2video -pix_fmt yuv420p -me_method epzs -threads 4 -r 30.000030 -g 45 -bf 2 -trellis 2 -cmp 2 -subcmp 2 -s 960x720 -b 2500k -bt 300k -async 1 -y "out.mpg" ![]() I have managed to to the job with simple ffmpeg -i "in.wmv" -c:v mpeg2video "out.mpg"īut the quality of the result is dreadful (clearly visible visual distortions are introduced) and the playback is not smooth (too slow at some moments). I have got a WMV (v9 (WMV3), 960x720, 30.000030 fps, planar 4:2:0 YUV, produced by PowerPoint 2010) file and need to convert it to MPEG2 - the only format my TVset can read from an USB flash drive (I have also tried MP4/h.264, AVI/XVID - nothing but MPEG2 works).
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