[--mute1 | --mute2 | --mix]"
echo ""
echo "Options:"
echo " --mute1 Mute the first video and use audio from the second."
echo " --mute2 Mute the second video and use audio from the first."
echo " --mix Mix the audio from both videos together."
echo ""
echo "Example:"
echo " ./merge_videos.sh left_cam.mp4 right_cam.mov --mute2"
}
function has_audio() {
ffprobe -v error -select_streams a:0 -show_entries stream=codec_type \
-of default=noprint_wrappers=1:nokey=1 "$1" 2>/dev/null | grep -q audio
}
if ! command -v ffmpeg &> /dev/null; then
echo "Error: ffmpeg is not installed or not in your system's PATH."
exit 1
fi
if ["$#" -ne 3]; then
show_usage
exit 1
fi
VIDEO1="$1"
VIDEO2="$2"
AUDIO_OPTION="$3"
if [! -f "$VIDEO1"]; then
echo "Error: Input file not found: '$VIDEO1'"
exit 1
fi
if [! -f "$VIDEO2"]; then
echo "Error: Input file not found: '$VIDEO2'"
exit 1
fi
HAS_AUDIO1=false
HAS_AUDIO2=false
has_audio "$VIDEO1" && HAS_AUDIO1=true
has_audio "$VIDEO2" && HAS_AUDIO2=true
echo "Video1 has audio: $HAS_AUDIO1"
echo "Video2 has audio: $HAS_AUDIO2"
echo "Inputs validated. Preparing to merge videos..."
VIDEO_FILTER="[0:v]scale=-2:${OUTPUT_HEIGHT}[v0];[1:v]scale=-2:${OUTPUT_HEIGHT}[v1];[v0][v1]hstack=inputs=2:shortest=0[v]"
case "$AUDIO_OPTION" in
--mute1)
echo "Using audio from the second video ('$VIDEO2')."
if $HAS_AUDIO2; then
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[sil1]; [sil1][1:a:0]amix=inputs=2[aout]"
else
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[aout]"
fi
;;
--mute2)
echo "Using audio from the first video ('$VIDEO1')."
if $HAS_AUDIO1; then
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[sil2]; [0:a:0][sil2]amix=inputs=2[aout]"
else
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[aout]"
fi
;;
--mix)
echo "Mixing audio from both videos."
if $HAS_AUDIO1 && $HAS_AUDIO2; then
FILTER_COMPLEX="${VIDEO_FILTER}; [0:a:0][1:a:0]amix=inputs=2[aout]"
elif $HAS_AUDIO1; then
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[sil2]; [0:a:0][sil2]amix=inputs=2[aout]"
elif $HAS_AUDIO2; then
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[sil1]; [sil1][1:a:0]amix=inputs=2[aout]"
else
FILTER_COMPLEX="${VIDEO_FILTER}; anullsrc=channel_layout=stereo:sample_rate=44100[aout]"
fi
;;
*)
echo "Error: Invalid audio option '$AUDIO_OPTION'."
show_usage
exit 1
;;
esac
TIMESTAMP=$(date +%Y%m%d_%H%M%S)
OUTPUT_FILE="${OUTPUT_FILE_PREFIX}_${TIMESTAMP}.mp4"
echo "Output will be saved to: $OUTPUT_FILE"
echo "Processing... This may take a while depending on video length and your computer's speed."
ffmpeg \
-i "$VIDEO1" \
-i "$VIDEO2" \
-filter_complex "$FILTER_COMPLEX" \
-map "[v]" \
-map "[aout]" \
-c:v libx264 \
-preset veryfast \
-crf 23 \
-c:a aac \
-b:a 192k \
-pix_fmt yuv420p \
-shortest \
-y \
"$OUTPUT_FILE"
if [$? -eq 0]; then
echo ""
echo "Success! Video merged successfully."
echo "Output file: $OUTPUT_FILE"
else
echo ""
echo "Error: FFmpeg failed to process the videos."
exit 1
fi
```
---
### Author:  [@slomo](https://discourse.gstreamer.org/u/slomo)
#### Post date: [August 19, 2025, 1:50pm UTC](https://discourse.gstreamer.org/t/gst-discoverer-reports-1x1-dimensions-for-valid-mp4-files/5309/4 "2025-08-19T13:50:34Z")
> [@altunenes](#):
>
> seems you need to see the video to understand this issue
Yeah there seems to be something specifically wrong with that video.
> [@altunenes](#):
>
> Unfortunately, the video is from a sensitive psychotherapy session, so I cannot share it on the web.
You could share the “headers” only, specifically the `moov` box which you can find either at the beginning (goes until the string `mdat` then), or at the very end of the file. That wouldn’t contain any sensitive media data.
---
### Author:  [@altunenes](https://discourse.gstreamer.org/u/altunenes)
#### Post date: [August 19, 2025, 10:19pm UTC](https://discourse.gstreamer.org/t/gst-discoverer-reports-1x1-dimensions-for-valid-mp4-files/5309/5 "2025-08-19T22:19:21Z")
GitLab issue:
> **[gst-discoverer reports 1x1 dimensions for "valid" MP4 files (#4608) · Issues...](https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/4608#note_3059002)**
>
> Hello all! I have MP4 files where gst-discoverer-1.0 reports video dimensions as 1x1 pixels, but the actual video content is 3840x1080. The affected videos:
---
### Author:  [@altunenes](https://discourse.gstreamer.org/u/altunenes)
#### Post date: [August 21, 2025, 8:39am UTC](https://discourse.gstreamer.org/t/gst-discoverer-reports-1x1-dimensions-for-valid-mp4-files/5309/6 "2025-08-21T08:39:05Z")
The problem has been fixed by @slomo [baseparse: Try harder to fixate caps based on upstream in default negotiation (!9593) · Merge requests · GStreamer / gstreamer · GitLab](https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/9593)
Thank you all!