commit 6f0544d3aaf02f7c1a204ec4d6234f777a41acf8 Author: Graeme Humphries Date: Fri Aug 23 13:36:29 2013 -0700 Initial release. diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..94a9ed0 --- /dev/null +++ b/LICENSE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +the GNU General Public License is intended to guarantee your freedom to +share and change all versions of a program--to make sure it remains free +software for all its users. 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If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/README.md b/README.md new file mode 100644 index 0000000..fbfe949 --- /dev/null +++ b/README.md @@ -0,0 +1,147 @@ +# dve - the distributed video encoder + +This is a small script to do distributed, high quality video encoding. + +The script: + +- breaks input video into chunks. +- distributes chunks to different servers via SSH. +- encodes those chunks in parallel. +- reassembles the chunks into final encoded video. + +Why do this? So you can encode video using the best settings possible, +and use as many machines as you have available to ensure it doesn't +take forever. ☺ + +## Usage + +By default, dve will just use your local host for encoding, which isn't likely to +improve performance. At a bare minimum, you should specify more than one host +to encode with: + + dve.sh -l host1,host2,host3 media/test.mp4 + +If you're using a statically linked ffmpeg binary (recommended), then you'll also +want to specify the path to that binary: + + dve.sh -e ~/bin/ffmpeg -l host1,host2,host3 media/test.mp4 + +After the encoding is completed and the chunks stitched back together, you +should end up with an output file named "test.mp4_new.mkv" in your current working +directory. You can adjust output naming, but note that the output container format +will currently always be mkv: + + dve.sh -s .encoded.mkv -e ~/bin/ffmpeg -l host1,host2,host3 media/test.mp4 + +## Benchmarks + +Hosts used for this benchmark were dual Xeon L5520 systems with 24GB of RAM, +16 HT cores per host. Input video file is a 4k resolution (4096x2304) test +clip, 3:47 in length. + +### ffmpeg on a single host + + $ time nice -n 10 ./ffmpeg -y -v error -stats -i test.mp4 -c:v libx264 -crf 20.0 -preset medium -c:a libvorbis -aq 5 -f matroska test.mkv + frame= 5459 fps=7.4 q=-1.0 Lsize= 530036kB time=00:03:47.43 bitrate=19091.2kbits/s + real 12m17.177s + user 182m57.340s + sys 0m36.240s + +### dve with 3 hosts + + $ time dve.sh -o "-c:v libx264 -crf 20.0 -preset medium -c:a libvorbis -aq 5" -l c1,c2,c3 test.mp4 + Creating chunks to encode + + Computers / CPU cores / Max jobs to run + 1:local / 2 / 1 + + Computer:jobs running/jobs completed/%of started jobs/Average seconds to complete + ETA: 1s 1left 1.57avg local:1/7/100%/1.6s + Running parallel encoding jobs + + Computers / CPU cores / Max jobs to run + 1:c1 / 16 / 1 + 2:c2 / 16 / 1 + 3:c3 / 16 / 1 + + Computer:jobs running/jobs completed/%of started jobs/Average seconds to complete + ETA: 380s 6left 64.00avg c1:1/1/40%/132.0s c2:1/0/20%/0.0s c3:1/1/40%/132.0s + Computer:jobs running/jobs completed/%of started jobs + ETA: 90s 2left 45.33avg 1:1/2/37%/138.0s 2:0/2/25%/138.0s 3:1/2/37%/138.0s + Computer:jobs running/jobs completed/%of started jobs/Average seconds to complete + ETA: 42s 1left 42.14avg c1:0/3/37%/99.7s c2:0/2/25%/149.5s c3:1/2/37%/149.5s + Computer:jobs running/jobs completed/%of started jobs + ETA: 50s 1left 50.29avg 1:0/3/37%/118.7s 2:0/2/25%/178.0s 3:1/2/37%/178.0s + Combining chunks into final video file + Cleaning up temporary working files + + real 6m17.075s + user 1m29.630s + sys 0m22.697s + + +### Summary + +dve has overhead, due to breaking the source file into chunks, transferring those chunks +across the network, retrieving the encoded chunks, and recombining into a new file. + +Given these limitations, a ~2x speed increase by using 3 encoding machines is +a reasonable improvement over using a single system. + +If you've got benchmarks using more hosts, please submit them! + +## Installation + +### SSH + +SSH is used by GNU parallel to distribute the jobs to target systems. +It's recommended that you use "ssh-keygen" and "ssh-copy-id" to +setup key based authentication to all your remote hosts. + +### Pre-reqs + +The following need to be installed on the host running this script: + +- [ffmpeg](http://johnvansickle.com/ffmpeg/) +- [GNU parallel](https://www.gnu.org/software/parallel/) + +It will automatically copy the encoder binary to the target systems and run +it there, but you will need to make sure any required shared libraries are installed +on the target system. + +It's recommended that you use the latest ffmpeg statically linked binaries (above), +which will also improve your chances of transcoding new / strange video formats. + +## Restrictions + +- currently only generates mkv containers on output. + +## ⚠ Known Issues + +Ubuntu ships the libav fork version ffmpeg wrapper instead of the actual ffmpeg +release. This version is missing many necessary features, including the +[concat demuxer](https://www.ffmpeg.org/faq.html#How-can-I-concatenate-video-files_003f) +used to stitch encoded chunks back together. + +For now, you should download and use the statically linked ffmpeg +binaries listed above. + +For more background about this fork, see: +[The FFmpeg/Libav situation](http://blog.pkh.me/p/13-the-ffmpeg-libav-situation.html) + +## License +dve is copyright 2013 by Graeme Humphries . + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with this program. If not, see the +[GNU licenses page](http://www.gnu.org/licenses/). diff --git a/dve b/dve new file mode 100755 index 0000000..1c0e9bb --- /dev/null +++ b/dve @@ -0,0 +1,154 @@ +#!/bin/bash + +ENC="ffmpeg" +OPTS="-c:v libx264 -crf 20.0 -preset veryslow -c:a libvorbis -aq 5" +SUFFIX="_new.mkv" +SERVERS="localhost" +CHUNKS=100 +MINLEN=30 +OUTDIR="$HOME/.dve" +VERBOSE="quiet" + +function usage() { + cat << EOF +usage: $0 [options] filename + +This script breaks a video file up into chunks and encodes them in parallel via SSH on +multiple hosts. + +OPTIONS: + -h this help message. + -c number of chunks to split input file into. (default=${CHUNKS}) + -e avconv binary to use. (default=${ENC}) + -l comma separated list of hosts to use to encode. (default=${SERVERS}) + -m min length of individual video chunks, in seconds. (default=${MINLEN}) + -o encoding options. (default=${OPTS}) + -s output file suffix. (default=${SUFFIX}) + -v verbose job output. (default=false) +EOF +} + +# check all required helper utils +function checkpaths() { + for cmd in avprobe parallel grep sed wc; do + if ! CMD=`which $cmd`; then + echo "$cmd not found." + exit 1 + fi + done + # check as absolute path first + if ! [ -x "$ENC" ]; then + # then check for something in $PATH + ENC="`which $ENC`" + if ! [ -x "$ENC" ]; then + echo "$ENC not executable." + exit 1 + fi + fi +} + +# returns total video length and optimal chunk length in seconds +function chunksize() { + if ! DURATION=`avprobe "$1" 2>&1 | grep Duration | grep -P -o "[0-9]+:[0-9]+:[0-9]+\.[0-9]+" | sed -r 's/\..+//g'`; then + echo "Couldn't find duration of \"$1\" using avprobe." + exit 1 + fi + declare -a DUR + DUR=(`echo ${DURATION} | sed -r 's/:/ /g'`) + + # strip leading zeros if present because bash can't handle it. + H=`echo ${DUR[0]} | sed 's/^0*//'` + M=`echo ${DUR[1]} | sed 's/^0*//'` + S=`echo ${DUR[2]} | sed 's/^0*//'` + # add extra second to length to account for subsecond variances + SECONDS=$((H*3600+M*60+S+1)) + LEN=$((SECONDS / CHUNKS)) + if [ $LEN -lt $MINLEN ]; then + LEN=$MINLEN + fi + echo ${SECONDS} ${LEN} +} + +checkpaths + +while getopts “hc:e:l:m:o:s:v” OPTION; do + case $OPTION in + h) + usage + exit 1 + ;; + c) + CHUNKS="$OPTARG" + ;; + e) + ENC="$OPTARG" + ;; + l) + SERVERS="$OPTARG" + ;; + m) + MINLEN="$OPTARG" + ;; + o) + OPTS="$OPTARG" + ;; + s) + SUFFIX="$OPTARG" + ;; + v) + VERBOSE="info" + ;; + ?) + usage + exit + ;; + esac +done +shift $((OPTIND-1)) + +if [ $# -lt 1 ]; then + usage + exit 1 +fi + +if ! mkdir -p ${OUTDIR}; then + echo "Couldn't create temp chunk output dir ${OUTDIR}." + exit 1 +fi + +declare -a TIMING +TIMING=( `chunksize "$1"` ) + +START=0 +CHUNKFILE="${OUTDIR}/chunkfile.txt" +rm "${CHUNKFILE}" 2> /dev/null +while [ $START -lt ${TIMING[0]} ]; do + printf "%06d\n" ${START} >> "${CHUNKFILE}" + START=$((START+TIMING[1])) +done + +NUMSERVERS=`echo ${SERVERS} | sed -r 's/,/ /g' | wc -w` + +echo "Creating chunks to encode" +cat "$CHUNKFILE" | parallel --gnu --eta -j 1 $ENC -y -v ${VERBOSE} -fflags +genpts -ss {} -i \"$1\" -t ${TIMING[1]} -c copy -f matroska ${OUTDIR}/chunk-{}.orig + +CWD=`pwd` +cd "$OUTDIR" + +cp "${ENC}" ./ffmpeg +echo "Running parallel encoding jobs" +PAR_OPTS="--gnu -j 1 -S ${SERVERS} --eta --retries 2 --nice 10" +PAR_OPTS="$PAR_OPTS --workdir ... --basefile ffmpeg --trc {.}.enc" +ENC_OPTS="-y -v ${VERBOSE} -i {} ${OPTS} -f matroska {.}.enc" + +parallel ${PAR_OPTS} ${HOME}/ffmpeg ${ENC_OPTS} ::: chunk-*.orig +echo "Combining chunks into final video file" +echo "ffconcat version 1.0" > concat.txt +for f in `ls chunk-*.enc | sort`; do + echo "file $f" >> concat.txt +done +${ENC} -y -v ${VERBOSE} -f concat -i concat.txt -f matroska -c copy "${CWD}"/"`basename \"$1\"`"${SUFFIX} + +echo "Cleaning up temporary working files" +rm -f "${OUTDIR}"/* +cd "$CWD"