Requirement
Install termux from
- play store
- github.com/termux/termux-app latest but require allow install from unknown source
open termux and update
$ pkg upgrade
install ffmpeg
$ pkg install ffmpeg nano
Allow termux to manage files
$ termux-setup-storage
Split a video by time
Target:
- every piece has 1 minutes 58 seconds
- resolution low 480
- output h264
- sound mono
command to convert '172967815750944 (1).mp4'
$ ffmpeg -i 172967815750944\ \(1\).mp4 -vf scale=-2:480 -r 25 -c:v libx264 -preset veryfast -crf 28 -ac 1 -c:a aac -b:a 96k -f segment -segment_time 118 -reset_timestamps 1 out_%03d.mp4
this command will create files with name starting with name out_[number].mp4
This is fastest way to split video into smaller size, but you need to write the long command. This is bash sh to split file to avoid write long command. Open nano and copy paste it, name it with mysplitvid.sh. Make it execute $ chmod u+x mysplitvid.sh.
#!/data/data/com.termux/files/usr/bin/bash
# Check input
if [ -z "$1" ]; then
echo "Usage: $0 inputvideo.mp4"
exit 1
fi
INPUT="$1"
BASENAME=$(basename "$INPUT" .mp4)
# Output directory (public, visible to other apps)
OUTDIR="/sdcard/Download/${BASENAME}_split"
mkdir -p "$OUTDIR"
# FFmpeg split + encode
ffmpeg -i "$INPUT" \
-vf scale=-2:480 \
-r 25 \
-c:v libx264 \
-preset veryfast \
-crf 28 \
-ac 1 \
-c:a aac \
-b:a 96k \
-f segment \
-segment_time 118 \
-reset_timestamps 1 \
"$OUTDIR/${BASENAME}_out%02d.mp4"
# Notify Android media scanner for all outputs
for file in "$OUTDIR"/*.mp4; do
am broadcast \
-a android.intent.action.MEDIA_SCANNER_SCAN_FILE \
-d "file://$file" >/dev/null
done
echo "✅ Done!"
echo "📂 Output folder: $OUTDIR”
Convert video h256 to social media
Target:
- Video Codec: H.264 (libx264)
- Audio Codec: AAC
- Pixel Format: yuv420p (Required for maximum compatibility)
- Audio Sample Rate: 48kHz or 44.1kHz
- Container: MP4
To convert an H.265 MP4 to a Twitter-compatible, highly compressed, lower-resolution MP4 using FFmpeg, you need to re-encode the video to H.264 video codec, AAC audio codec, a maximum resolution of 1280x720, and a lower bitrate/higher CRF value.
Assume your file is inputfile.mp4 and located at Download folder in your Android. Here are command to convert your video to make compatible for social media. Currently social media do not support high compression like h265.
~/ $ cd ~/storage
~/storage $ ls
audiobooks downloads movies podcasts
dcim external-0 music shared
documents media-0 pictures
~/storage $ cd downloads
~/storage/downloads $ ls *.mp4
inputfile.mp4
~/storage/downloads $ ffmpeg -i inputfile.mp4 -c:v libx264 -crf 28 -preset medium -vf "scale=1280:720,format=yuv420p" -c:a aac -b:a 128k -movflags faststart output.mp4
...
This is bash sh to split file to avoid write long command. Open nano and copy paste it, name it with myconverth265.sh. Make it execute $ chmod u+x myconverth265.sh.
#!/data/data/com.termux/files/usr/bin/bash
# Usage: ./convert_video.sh videoinput.mp4
INPUT="$1"
if [ -z "$INPUT" ]; then
echo "Usage: $0 input_video.mp4"
exit 1
fi
# Remove extension
BASENAME=$(basename "$INPUT")
NAME="${BASENAME%.*}"
# Output path (shared storage)
OUTPUT="/sdcard/Download/${NAME}_out.mp4"
echo "Converting $INPUT → $OUTPUT"
ffmpeg -y -i "$INPUT" \
-c:v libx264 \
-crf 28 \
-preset medium \
-vf "scale=1280:720,format=yuv420p" \
-c:a aac \
-b:a 128k \
-movflags faststart \
"$OUTPUT"
# Notify Android media scanner
am broadcast \
-a android.intent.action.MEDIA_SCANNER_SCAN_FILE \
-d "file://$OUTPUT"
echo "✅ Done! Video available in Gallery / Files / Photos”
Make your output video accessible by other application
Your output file is owned by Termux. To make it accessible by other applications e.g. photos, files, etc, you can try these option
• move it to Movies or Download folder
$ mv out_*.mp4 /storage/emulated/0/Movies/
• Force android system to scan your output
$ am broadcast -a android.intent.action.MEDIA_SCANNER_SCAN_FILE -d file:///sdcard/Download/output.mp4
