Trimming and joining media files using ffmpeg

I am trying to remove a segment (00:26:00 - 00:32:30) from a video file input.mp4.
Since there is no way to do that directly using ffmpeg (as far as I know), I am instead cutting the segments which I want in the output and then concatenating them.

After searching a bit, I've found that there are 2 ways to do this:

• Using trim as mentioned in this answer
• Using seek as mentioned in this answer.

Unfortunately, both these methods are failing for me.

I am going to explain the steps I performed in both the methods:

1. Using trim:

EDIT: This method works now; skip to the second method instead.

Command used:

ffmpeg -i input.mp4 -filter_complex \"[0:v]trim=duration=00:26:00[a]; \[0:v]trim=start=00:32:30,setpts=PTS-STARTPTS[b]; \[a][b]concat[c]" -map [c] out.mp4

Command output: Link

The output file is less than 1 minutes long and is of just 6.8 MB, whereas the input file was 900 MB.

2. Using seek

Command used:

# Cut first wanted segmentffmpeg -ss 00:00:00 -i input.mp4 -t 00:26:00 -c copy -avoid_negative_ts 1 first.mp4# Cut second wanted segmentffmpeg -ss 00:32:30 -i input.mp4 -c copy -avoid_negative_ts 1 second.mp4# Combine all the wanted segmentsffmpeg -f concat -i input.txt -c copy output.mp4

where input.txt contains:

file first.mp4file second.mp4

Command output: Link (The error is mentioned on line 90: input.txt: Invalid argument)

The output file I get in this case is only about 500 MB (input file being 900 MB), and contains first video + first few minutes of the second video.

My system details:

• Ubuntu 14.04

• ffmpeg version: Link

EDIT:

Method 1 using trim is now working, thanks to @Mulvya's comment regarding writing seconds as the unit of time instead of the HH:MM:SS notation as it is broken.

New command:

ffmpeg -i input.mp4 -filter_complex \"[0:v]trim=duration=1500[av]; \ [0:a]atrim=duration=1500[aa];\ [0:v]trim=start=1980,setpts=PTS-STARTPTS[bv]; \ [0:a]atrim=start=1980,asetpts=PTS-STARTPTS[ba];\ [av][bv]concat[outv]; [aa][ba]concat=v=0:a=1[outa]" \ -map [outv] -map [outa] out.mp4

But, I still want to know what's wrong with the second method.