/tech/ - Technology★

>>1007429 (OP)

man ffmpeg

>vp8

>>1007429 (OP)

>https://trac.ffmpeg.org/wiki/Encode/VP9

First link for "ffmpeg webm" in startpage. You're a retarded niggerfaggot.

>>1007430

>man ffmpeg

You meant ffmpeg-codec, right?

>>1007429 (OP)

Shit guide.

>>1007442

That one is okay but here is one with all flags optimal right out of the box:

Section Constant Quality Recommended Settings in http://wiki.webmproject.org/ffmpeg/vp9-encoding-guide

>>1007443

Nah, it's a bad guide, the "best" section is the equivalent of the placebo preset for x264. Personally, I use

ffmpeg -i "$1" -ss "$sdur" -t "$dur" -map 0:v:0 -map 0:a:$astream? \
        -c:v libvpx-vp9 -auto-alt-ref 1 -lag-in-frames 25 -speed 1 -tile-columns 2 \
        -threads 2 -b:v $vrate -pix_fmt yuv420p \
        -c:a libopus -ac 2 -b:a $arate \
        -vf "$filterchain" -sn -pass 1 -f webm -y /dev/null

The real advice to give is: make sure you use the latest libvpx, because the improvements are massive.

>>1007455

>the "best" section is the equivalent of the placebo preset for x264

Not exactly. It is slow but it also prevents quantization from jumping all over the place.

#!/usr/bin/env sh

trap finish 1 2 14 15

finish ()
{
    command rm -f -- "${PASSLOG}-0.log"
    unset encode error finish help \
          INPUT LOSSLESS NAME OPTARG OUTPUT OVERWRITE PASSLOG QUALITY THREADS TMP0 TMP1
    exit $1
}

help ()
{
    command cat << EOF
USAGE: $NAME [OPTION]... INPUT [OUTPUT]
Encode a video with VP9 codec using FFmpeg.

OPTIONS:
  -h : display this help and exit
  -q : set the encoding quality
       between 0 and 63, 0 is lossless, default is 30
  -t : set the number of threads to use
  -f : do not prompt before overwriting
EOF
    finish
}

error ()
{
    printf "%s: %s -- '%s'\n" "$NAME" "$1" "$OPTARG" >&2
    finish 1
}

encode ()
{
    printf 'Pass #%d...\n' $1
    case "$1" in
        1) TMP0='-y'
           TMP1='/dev/null'
           ;;
        2) TMP0="$OVERWRITE"
           TMP1="$OUTPUT"
           ;;
    esac
    command ffmpeg -v error -stats $TMP0 \
                   -i "$INPUT" -map 0:v:0 -map_chapters -1 -map_metadata -1 \
                   -sws_flags lanczos+accurate_rnd+full_chroma_int+bitexact \
                   -c:v libvpx-vp9 -b:v 0 -auto-alt-ref 1 -lag-in-frames 25 \
                   -tile-columns 0 -frame-parallel 0 -aq-mode none -row-mt 1 \
                   -cpu-used 0 -deadline best \
                   -threads $THREADS -crf $QUALITY -lossless $LOSSLESS \
                   -pass $1 -passlogfile "$PASSLOG" -f ivf -bitexact -- "$TMP1"
    return $?
}

NAME="`basename -- "$0"`"
THREADS=`grep -c ^processor /proc/cpuinfo`
QUALITY=30
LOSSLESS=0

while getopts hfq:t: TMP0; do
    case "$TMP0" in
        h) help ;;
        f) OVERWRITE='-y' ;;
        q) case "$OPTARG" in
               0)  QUALITY=0
                   LOSSLESS=1
                   ;;
               [1-9]|[1-5][0-9]|6[0-3])
                   QUALITY=$OPTARG
                   ;;
               *)  error 'incorrect encoding quality' ;;
           esac
           ;;
        t) case "$OPTARG" in
               [1-9]|[1-9][0-9])
                   if [ $OPTARG -gt $THREADS ]; then
                       error 'not enough CPU cores'
                   else
                       THREADS=$OPTARG
                   fi
                   ;;
               *)  error 'incorrect number of threads' ;;
           esac
           ;;
    esac
done
shift $((OPTIND-1))
unset TMP0 OPTARG

if [ -z "$1" ]; then
    help
else
    INPUT="$1"
fi
if [ -z "$2" ]; then
    OUTPUT="${INPUT%.*}.ivf"
else
    OUTPUT="$2"
fi
PASSLOG="`basename -- "$OUTPUT"`"
PASSLOG="${XDG_CACHE_HOME:-/tmp}/${PASSLOG%.*}"

encode 1 && encode 2

finish $?

>>1007455

>"best" section

I did refer solely to the Constant Quality Recommended Settings

see >>1007443

>>1007429 (OP)

They have some good stuff at >>>/webm/

>>1007473

Pretty okay script (but don't use backticks, they're horrible to nest). Here's mine: https://repo.or.cz/q3cpma-shell-scripts.git/blob/HEAD:/webm.sh

>How are you supposed to find new commands to fiddle around with in FFmpeg?

QTDDTOT

>>>/g/

RTFM

pick one

start off small and develop your own script as you go.

My current incantation is over 300 loc, calculates bit rates, and formats automatically, and plays a tune when finished.