Makefile merge two videos vertically with FFmpeg

00-README-ffmpeg-merge-makefile-sample.md

Description

Makefile that merge two videos vertically with FFmpeg.

Tools

• youtube-dl
• FFmpeg
• ffprobe

Files

• chiko_src.mov (1920x1080, 28s) -> chiko_trimmed.mov (1370x700, 2s)
• Youtube -> hazuki_src.mp4 (640x360, 60s) -> hazuki_trimmed.mp4 (640x360, 2s)
• chiko_trimmed.mov + hazuki_trimmed.mp4 -> merged.mp4 (640x720, 2s) -> merged.gif

chiko_src.mov is not uploaded and only in my iPhone.

Makefile

# inspect tasks:
#   inspect_chiko               : shows chiko mov file inspection
#   inspect_hazuki_online       : shows youtube available download formats
#   inspect_hazuki_offline      : shows hazuki mp4 file inspection

CHIKO_SRC	:= chiko_src.mov
CHIKO_TRIMMED	:= chiko_trimmed.mov
CHIKO_EYECATCH_START	:= 23
CHIKO_EYECATCH_DURATION	:= 2
CHIKO_CROP	:= "w=1370:h=700:x=234:y=200"

HAZUKI_SRC	:= hazuki_src.mp4
HAZUKI_SRC_URL	:= "https://www.youtube.com/watch?v=0Efumx0B9VI"
HAZUKI_TRIMMED	:= hazuki_trimmed.mov
HAZUKI_EYECATCH_START	:= 58
HAZUKI_EYECATCH_DURATION	:= 3

# 134 means 640x360 mp4 in that movie
HAZUKI_DOWNLOAD_FORMAT	:= 134

MERGED	:= merged.mp4
MERGED_GIF	:= merged.gif

CLEAN	:= ${CHIKO_TRIMMED} ${HAZUKI_SRC} ${HAZUKI_TRIMMED} \
	${MERGED} ${MERGED_GIF}

all:	${MERGED_GIF}

clean:
	rm ${CLEAN}

.PHONY:	inspect_chiko
inspect_chiko:
	ffprobe ${CHIKO_SRC}

.PHONY:	inspect_hazuki_online
inspect_hazuki_online:
	youtube-dl -F "${HAZUKI_SRC_URL}"

.PHONY:	inspect_hazuki_offline
inspect_hazuki_offline:
	ffprobe ${HAZUKI_SRC}

${HAZUKI_SRC}:
	youtube-dl -f "${HAZUKI_DOWNLOAD_FORMAT}" -o "${HAZUKI_SRC}" \
	"${HAZUKI_SRC_URL}"

${CHIKO_TRIMMED}:	${CHIKO_SRC}
	ffmpeg -i ${CHIKO_SRC} \
	-ss ${CHIKO_EYECATCH_START} -t ${CHIKO_EYECATCH_DURATION} \
	-vf crop=${CHIKO_CROP} ${CHIKO_TRIMMED}

${HAZUKI_TRIMMED}:	${HAZUKI_SRC}
	ffmpeg -i ${HAZUKI_SRC} \
	-ss ${HAZUKI_EYECATCH_START} -t ${HAZUKI_EYECATCH_DURATION} \
	${HAZUKI_TRIMMED}

${MERGED}: ${CHIKO_TRIMMED} ${HAZUKI_TRIMMED}
	ffmpeg -i ${CHIKO_TRIMMED} -i ${HAZUKI_TRIMMED} \
	-filter_complex " \
	nullsrc=size=640x720 [base]; \
	[0:v] setpts=PTS-STARTPTS, scale=640x360 [upper]; \
	[1:v] setpts=PTS-STARTPTS, scale=640x360 [lower]; \
	[base][upper] overlay=shortest=1 [tmp1]; \
	[tmp1][lower] overlay=shortest=1:y=360 \
	" \
	-y -c:v libx264 ${MERGED}

${MERGED_GIF}: ${MERGED}
	ffmpeg -i ${MERGED} -an -r 15 -pix_fmt rgb24 -f gif -y ${MERGED_GIF}