我解决了这个问题（但是它并不完全兼容每个现代浏览器，例如在我的 Linux 版本的 Firefox 上，音频无法播放）：
#!/bin/bash
# THIS SCRIPT CONVERTS EVERY MP4 (IN THE CURRENT FOLDER AND SUBFOLDER) TO A MULTI-BITRATE VIDEO IN MP4-DASH
# For each file "videoname.mp4" it creates a folder "dash_videoname" containing a dash manifest file "stream.mpd" and subfolders containing video segments.
# Validation tool:
# http://dashif.org/conformance.html
# Documentation:
# https://tdngan.wordpress.com/2016/11/17/how-to-encode-multi-bitrate-videos-in-mpeg-dash-for-mse-based-media-players/
# Remember to add the following mime-types (uncommented) to .htaccess:
# AddType video/mp4 m4s
# AddType application/dash+xml mpd
# DASH-264 JavaScript Reference Client
# https://github.com/Dash-Industry-Forum/dash.js
# https://github.com/Dash-Industry-Forum/dash.js/wiki
MYDIR=$(dirname $(readlink -f ${BASH_SOURCE[0]}))
SAVEDIR=$(pwd)
# Check programs
if [ -z "$(which ffmpeg)" ]; then
echo "Error: ffmpeg is not installed"
exit 1
fi
if [ -z "$(which MP4Box)" ]; then
echo "Error: MP4Box is not installed"
exit 1
fi
cd "$MYDIR"
TARGET_FILES=$(find ./ -type f -name "*.mp4")
for f in $TARGET_FILES
do
f=$(basename "$f") # fullname of the file
f="${f%.*}" # name without extension
if [ ! -d "dash_${f}" ]; then
echo "Converting \"$f\" to multi-bitrate video in MPEG-DASH"
ffmpeg -y -i "${f}.mp4" -c:a libfdk_aac -ac 2 -ab 128k -vn "${f}_audio.m4a"
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 1500k -vf "scale=-2:720" -f mp4 -pass 1 -y /dev/null
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 1500k -vf "scale=-2:720" -f mp4 -pass 2 "${f}_1500.mp4"
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 800k -vf "scale=-2:540" -f mp4 -pass 1 -y /dev/null
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 800k -vf "scale=-2:540" -f mp4 -pass 2 "${f}_800.mp4"
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 400k -vf "scale=-2:360" -f mp4 -pass 1 -y /dev/null
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 400k -vf "scale=-2:360" -f mp4 -pass 2 "${f}_400.mp4"
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 200k -vf "scale=-2:180" -f mp4 -pass 1 -y /dev/null
ffmpeg -y -i "${f}.mp4" -an -c:v libx264 -x264opts 'keyint=24:min-keyint=24:no-scenecut' -b:v 200k -vf "scale=-2:180" -f mp4 -pass 2 "${f}_200.mp4"
rm -f ffmpeg*log*
MP4Box -dash 2000 -rap -frag-rap -profile onDemand "${f}_1500.mp4" "${f}_800.mp4" "${f}_400.mp4" "${f}_200.mp4" "${f}_audio.m4a" -out "${f}_MP4.mpd"
rm "${f}_1500.mp4" "${f}_800.mp4" "${f}_400.mp4" "${f}_200.mp4" "${f}_audio.m4a"
fi
done
cd "$SAVEDIR"
我还尝试了 VP9 而不是 h.264，但在这种情况下，与所有浏览器都不兼容（在我的 Linux 发行版中，它只能在 Firefox 上正常播放，而在 Chrome 上根本无法播放）：
#!/bin/bash
MYDIR=$(dirname $(readlink -f ${BASH_SOURCE[0]}))
SAVEDIR=$(pwd)
# Controlla che i programmi richiesti siano installati
if [ -z "$(which ffmpeg)" ]; then
echo "Errore: ffmpeg non e' installato"
exit 1
fi
cd "$MYDIR"
TARGET_FILES=$(find ./ -type f -name "*.mp4")
for f in $TARGET_FILES
do
f=$(basename "$f") # memorizza il nome completo del file
f="${f%.*}" # toglie l'estensione
if [ ! -f "${f}.mpd" ]; then
echo "Converto il file \"$f\" in Adaptive WebM using DASH"
echo "Riferimenti: http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash"
# http://wiki.webmproject.org/adaptive-streaming/instructions-to-playback-adaptive-webm-using-dash
VP9_DASH_PARAMS="-tile-columns 4 -frame-parallel 1"
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:90 -b:v 250k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 1 -y /dev/null
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:90 -b:v 250k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 2 "${f}_160px_250k.webm"
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:180 -b:v 500k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 1 -y /dev/null
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:180 -b:v 500k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 2 "${f}_320px_500k.webm"
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:360 -b:v 750k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 1 -y /dev/null
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:360 -b:v 750k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 2 "${f}_640px_750k.webm"
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:360 -b:v 1000k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 1 -y /dev/null
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:360 -b:v 1000k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 2 "${f}_640px_1000k.webm"
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:720 -b:v 1500k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 1 -y /dev/null
ffmpeg -i "${f}.mp4" -c:v libvpx-vp9 -vf scale=-1:720 -b:v 1500k -keyint_min 150 -g 150 ${VP9_DASH_PARAMS} -an -f webm -dash 1 -pass 2 "${f}_1280px_1500k.webm"
ffmpeg -i "${f}.mp4" -c:a libvorbis -b:a 128k -vn -f webm -dash 1 "${f}_audio_128k.webm"
rm -f ffmpeg*.log
ffmpeg \
-f webm_dash_manifest -i "${f}_160px_250k.webm" \
-f webm_dash_manifest -i "${f}_320px_500k.webm" \
-f webm_dash_manifest -i "${f}_640px_750k.webm" \
-f webm_dash_manifest -i "${f}_640px_1000k.webm" \
-f webm_dash_manifest -i "${f}_1280px_1500k.webm" \
-f webm_dash_manifest -i "${f}_audio_128k.webm" \
-c copy -map 0 -map 1 -map 2 -map 3 -map 4 -map 5 \
-f webm_dash_manifest \
-adaptation_sets "id=0,streams=0,1,2,3,4 id=1,streams=5" \
"${f}.mpd"
fi
done
cd "$SAVEDIR"
我没有找到向所有浏览器提供音频/视频内容的方法。我已经完成了我的测试：
<!DOCTYPE html>
<html>
<head>
<script src="http://cdn.dashjs.org/latest/dash.all.min.js"></script>
<style>
video {
width: 640px;
height: 360px;
}
</style>
</head>
<body>
<div>
<video data-dashjs-player autoplay src="test.mpd" controls></video>
</div>
</body>
</html>
