WinFF for Rockbox : file size doubled

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hack and hack
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Iscritto: 04/02/2015

I converted a 26 Mo .mkv using a preset for Rockbox in WinFF.
The converted .mpg is 52 Mo, and the quality is less than the original (which is normal, plus is good enough for the targeted device).

Do you know any way to fix this without reducing image quality (and hopefully sound as well) ?

Here's the command in the FFmpeg tab, wich is the default for the preset iPod video fullscreen:
/usr/bin/ffmpeg -y -i "/path/to/originalfile.mkv" -acodec libmp3lame -b:a 128k -ar 44100 -vcodec mpeg2video -filter:v scale=w=320:h=240 -b:v 400k -strict -1 "/path/to/convertedfile.mpg"

Handbrake didn't work (has wrappers in mp4 and mkv, even for mpeg-2).

hack and hack
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Iscritto: 04/02/2015

An attempt with another file trimmed about 10 Mo from the original which was around 90 Mo. That one is mp4 though.
That's more like it, although the other file I tried still doubled in size (2nd attempt).

Would this mean that the .mkv compresses the original file this much ? And that all is normal ?

aloniv

I am a translator!

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Iscritto: 01/11/2011

Rockbox firmware plays back the video using the CPU and thus chose a non-CPU intensive format (MPEG) for playback. If you convert a H264 or VP9 video file to MPEG-1 or MPEG-2 while retaining most of the quality the resulting file size will usually be larger.

hack and hack
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Iscritto: 04/02/2015

Thank you aloniv, understood.