Encoding to .FLV but just black in converted file??? Help me please!!!!

[mkettle]

Hi everyone, please help me!

I've downloaded the ffMpeg X program and I'm trying to convert a quicktime movie file into a FLash media file but it's just not working. I think I've downloaded the program correctly as I've followed all the things mentioned on the forum and when I convert to another format it works.

HOWVER, when going from a Mpeg 1 movie file and converting to FLV file it converts extremely quickly (like 2 seconds) and when I open the file it is black with no sound or image. Please help I've tried exporting the file as a variety of formats but always the same with FLV.

I get the following information when I open it up:

FFmpeg version CVS, Copyright (c) 2000-2004 Fabrice Bellard
Mac OSX universal build for ffmpegX
Sun Feb 15 23:22:38 GMT 2009
libavutil version: 49.0.0
libavcodec version: 51.9.0
libavformat version: 50.4.0
Input #0, mpeg, from '/Hush-Rambert - HUSH-MPEG-1 .mpg':
Duration: 00:26:46.8, start: 0.766200, bitrate: 2086 kb/s
Stream #0.0[0x1c0]: Audio: mp2, 48000 Hz, stereo, 192 kb/s
Stream #0.1[0x1e0], 25.00 fps(r): Video: mpeg1video, yuv420p, 352x288, 1850 kb/s
Codec type mismatch for mapping #0.0 -> #0.0

Any insights would be massively appreciated!
Thank you!
Michelle

[Case]

Hi Michelle,
Welcome to our little corner of the 'net.

The last line in your log is the actual error message. "Codec type mismatch for mapping #0.0 -> #0.0" means that ffmpegX tries to convert the source audio (input stream #0.0) to target video (output stream #0.0). That fails because it wants a video codec to convert to video, and audio to audio. It seems your source file is somewhat odd, in that the audio is listed (#0.0) before the video (#0.1), when ffmpeg likes to see it the other way around.

ffmpeg's solution to this is to customize the stream mapping, so it can be reversed (#0.1 -> #0.0 and #0.0 -> #0.1). In ffmpegX's interface, this can be done with the "Invert mapping" checkbox in the Audio tab.
Unfortunately, conversions to FLV don't work well with inverted stream mapping: it introduces a stuttering issue with Flash Player.

For converting with ffmpegX to FLV from .mpg files with the audio stream listed before the video stream, I would recommend re-muxing: Demux into two files (video-only and audio-only), then mux them back again. The re-muxed file should be the same as the original, except for the stream order. The remuxed file should convert fine to FLV without needing to invert stream mapping: no more "Codec type mismatch for mapping"-errors.

(I've mentioned manually changing the stream order with QuickTime Pro in other topics on this forum, but that doesn't work for .mpg files.)

ffmpegX has demux and mux tools in the Tools tab, although I like MPEG Streamclip's demuxing better, as it can overcome some file errors, if present.

Let us know how it went, good or bad. Or if the above wasn't insightful enough.