ffmpeg-timelapse

#!/bin/bash

set -eu

run() {
    echo >&2 "+ $*"
    "$@"
}

usage() {
    cat >&2 <<EOM
usage: $(basename "$0") INPUT_GLOB OUTPUT.MP4

NB: be sure to quote the INPUT_GLOB

Example:

    $(basename "$0") 'photos/*.jpg' timelapse.mp4

EOM
}

if [ $# -ne 2 ]; then
    usage
    exit 1
fi

input_glob="$1"
output="$2"

OUTPUT_RESOLUTION="${OUTPUT_RESOLUTION-}"
IN_FRAME_RATE="${IN_FRAME_RATE-15}"
WATERMARK="${WATERMARK-}"
QUIET="${QUIET-}"

opts=()

if [ -n "$OUTPUT_RESOLUTION" ]; then
    opts+=(-s:v "$OUTPUT_RESOLUTION")
fi

if [ -n "$WATERMARK" ]; then
    FONTFILE="${FONTFILE-/usr/share/fonts/truetype/roboto/Roboto-Regular.ttf}"
    if [ -n "$OUTPUT_RESOLUTION" ]; then
        # HACK: assume input appropriate for 2592x1944
        opts+=(-vf "drawtext=fontfile=$FONTFILE: text='$WATERMARK': fontcolor=white@0.8: fontsize=96: x=(w-text_w-20): y=20: borderw=2")
    else
        # HACK: assume 640x480
        opts+=(-vf "drawtext=fontfile=$FONTFILE: text='$WATERMARK': fontcolor=white@0.8: fontsize=24: x=(w-text_w-8): y=8: borderw=1")
    fi
fi

if [ -n "$QUIET" ]; then
    opts+=(-nostats)
fi

run ffmpeg -f image2 -framerate "$IN_FRAME_RATE" -pattern_type glob \
    -i "$input_glob" -r 30 "${opts[@]}" -vcodec libx264 "$output"