From 13724f55c83a996671df47ab9b5c504dc765d400 Mon Sep 17 00:00:00 2001 From: Moritz Bunkus Date: Wed, 23 Apr 2003 06:24:08 +0000 Subject: [PATCH] Updated the overhead factor. Included a note about low disk space and MP3 encoding. --- README | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/README b/README index ee302e8aa..db78dc54a 100644 --- a/README +++ b/README @@ -70,6 +70,11 @@ video frame numbers: mencoder -dvd 1 -ovc frameno -oac pcm -o frameno.avi +If you're low on disk space and can invest a bit more time then you +tell mencoder to encode to MP3 instead: + +mencoder -dvd 1 -ovc frameno -oac mp3lame -lameopts br=32 -o frameno.avi + b) Extract the audio again, this time to a plain WAV file: mplayer -dvd 1 -vc dummy -vo null -hardframedrop -ao pcm -aofile audio.wav @@ -87,12 +92,13 @@ oggenc -q3 -oaudio-q3.ogg audio.wav e) Somehow calculate the bitrate for your video. Use something like... -video_size = (target_size - audio-size) / 1.0115 +video_size = (target_size - audio-size) / 1.005 video_bitrate = video_size / length / 1024 * 8 target_size, audio_size in bytes length in seconds -1.0115 is the overhead caused by putting the streams into an Matroska file. +1.005 is the overhead caused by putting the streams into an Matroska file + (about 0.5%, that's correct ;)). video_bitrate will be in kbit/s f) Use the two-pass encoding for the video: @@ -111,4 +117,4 @@ g) Merge: mkvmerge -o movie.mkv -A movie.avi audio-q3.ogg --A is necessary in order to avoid copying the raw PCM audio as well. +-A is necessary in order to avoid copying the raw PCM (or MP3) audio as well.