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2026-01-03T05:28:00Z

by freem.ai...

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{{DISPLAYTITLE:FFmpeg video cut guide}}

''This conversation was exported from ChatGPT''<ref>{{cite web|title=FFmpeg video cut guide|url=https://chatgpt.com/share/6957d2e8-b738-8008-987a-09a5d9f29bc8|publisher=ChatGPT|access-date=2026-01-02}}</ref>

== gpt-5-2-thinking ==
=== User: ffmpeg cut from video the timestamsp 01:02 - 02:13 + 03:17 - 05:26 + 09:21 - 09:28 + 09:44 - 10:04 into a single video ===
ffmpeg cut from video the timestamsp 01:02 - 02:13 + 03:17 - 05:26 + 09:21 - 09:28 + 09:44 - 10:04 into a single video

=== Assistant: Here are two good ways to do it. ===
Here are two good ways to do it.

==== This will cut exactly at those timestamps and stitch into one file. ====

<syntaxhighlight lang="bash">ffmpeg -i input.mp4 -filter_complex \
"[0:v]trim=start=62:end=133,setpts=PTS-STARTPTS[v0]; \
[0:a]atrim=start=62:end=133,asetpts=PTS-STARTPTS[a0]; \
[0:v]trim=start=197:end=326,setpts=PTS-STARTPTS[v1]; \
[0:a]atrim=start=197:end=326,asetpts=PTS-STARTPTS[a1]; \
[0:v]trim=start=561:end=568,setpts=PTS-STARTPTS[v2]; \
[0:a]atrim=start=561:end=568,asetpts=PTS-STARTPTS[a2]; \
[0:v]trim=start=584:end=604,setpts=PTS-STARTPTS[v3]; \
[0:a]atrim=start=584:end=604,asetpts=PTS-STARTPTS[a3]; \
[v0][a0][v1][a1][v2][a2][v3][a3]concat=n=4:v=1:a=1[v][a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -crf 20 -preset medium \
-c:a aac -b:a 160k \
-movflags +faststart \
output.mp4

</syntaxhighlight>

Timestamps converted to seconds:
* 01:02–02:13 → 62–133
* 03:17–05:26 → 197–326
* 09:21–09:28 → 561–568
* 09:44–10:04 → 584–604

:

==== This tries to avoid re-encoding. Often works, but accuracy depends on keyframes. ====

<syntaxhighlight lang="bash">ffmpeg -ss 01:02 -to 02:13 -i input.mp4 -c copy -avoid_negative_ts 1 part1.mp4
ffmpeg -ss 03:17 -to 05:26 -i input.mp4 -c copy -avoid_negative_ts 1 part2.mp4
ffmpeg -ss 09:21 -to 09:28 -i input.mp4 -c copy -avoid_negative_ts 1 part3.mp4
ffmpeg -ss 09:44 -to 10:04 -i input.mp4 -c copy -avoid_negative_ts 1 part4.mp4

printf "file 'part1.mp4'\nfile 'part2.mp4'\nfile 'part3.mp4'\nfile 'part4.mp4'\n" > list.txt
ffmpeg -f concat -safe 0 -i list.txt -c copy output.mp4

</syntaxhighlight>

If you tell me whether you want exact cuts (Option A) or fast/no re-encode (Option B), I can tailor the command for your codec/container constraints.

=== User: actually i want them separate in order to check them ===
actually i want them separate in order to check them
also, i want to be able to cut up to miliseconds, if needed

=== Assistant: Got it — make separate clips, and allow millisecond precision. ===
Got it — make separate clips, and allow millisecond precision.

==== Use -ss/-to with input seeking (accurate) and re-encode. Put -ss after -i. ====

===== <syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:01:02.000 -to 00:02:13.000 \ =====
-c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k \
-movflags +faststart clip_01_0102-0213.mp4

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:03:17.000 -to 00:05:26.000 \ =====
-c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k \
-movflags +faststart clip_02_0317-0526.mp4

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:09:21.000 -to 00:09:28.000 \ =====
-c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k \
-movflags +faststart clip_03_0921-0928.mp4

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:09:44.000 -to 00:10:04.000 \ =====
-c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k \
-movflags +faststart clip_04_0944-1004.mp4

</syntaxhighlight>

Millisecond edits: just change .000 to whatever you need, e.g. 00:03:17.237.

==== If you must keep original video quality, the only way to be frame/ms-accurate without re-encoding is basically impossible — stream copy can only cut cleanly on keyframes and audio packet boundaries. ====

However, you can do “almost-original” by re-encoding only around cut points, but that’s more complex and usually not worth it unless quality is critical.

==== With -ss after -i (like above), -to is treated as an end timestamp in the input timeline (works well for human timestamps). ====

If you ever prefer “duration”, use -t instead:

<syntaxhighlight lang="bash"># from 01:02 for 71 seconds
ffmpeg -i input.mp4 -ss 00:01:02.000 -t 00:01:11.000 ...

</syntaxhighlight>

==== <syntaxhighlight lang="bash">in="input.mp4" ====

ffmpeg -i "$in" -ss 00:01:02.000 -to 00:02:13.000 -c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k -movflags +faststart clip_01.mp4
ffmpeg -i "$in" -ss 00:03:17.000 -to 00:05:26.000 -c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k -movflags +faststart clip_02.mp4
ffmpeg -i "$in" -ss 00:09:21.000 -to 00:09:28.000 -c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k -movflags +faststart clip_03.mp4
ffmpeg -i "$in" -ss 00:09:44.000 -to 00:10:04.000 -c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k -movflags +faststart clip_04.mp4

</syntaxhighlight>

If you tell me your input codecs (paste ffprobe -hide_banner -i input.mp4), I can adjust settings to either keep the same FPS/resolution, preserve 5.1 audio, or speed it up with hardware encoding (NVENC/QSV/VAAPI).

=== User: why are "-c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k -movflags +faststart" needed? ===
why are "-c:v libx264 -crf 20 -preset medium -c:a aac -b:a 160k -movflags +faststart" needed?

=== Assistant: They’re not required to cut — they’re just the “safe defaults” that make the output widely playable and keep the cut ac… ===
They’re not required to cut — they’re just the “safe defaults” that make the output widely playable and keep the cut accurate.

Here’s what each one does, and what happens if you remove it:

===== Chooses the video encoder (H.264). =====
* If you don’t specify -c:v, ffmpeg will pick a default encoder for the output container (often still H.264, but not guaranteed).
* You could also use -c:v copy to avoid re-encoding, but then your cut won’t be millisecond-accurate (it’ll snap to keyframes / packet boundaries).

===== Quality target for x264 (“constant quality” mode). Lower = higher quality/bigger file; higher = lower quality/smaller file. =====
* Not required; if omitted, x264 uses its default CRF (commonly 23), which is a bit lower quality.
* Typical range: 18–23.

===== Encoding speed vs compression efficiency. =====
* Not required; x264 defaults to medium anyway.
* Slower presets = smaller file for same quality (but take longer).

===== Re-encodes audio to AAC at 160 kbps. =====
* Not required; ffmpeg might pick AAC anyway, but again not guaranteed.
* If your source audio is already AAC and you don’t need frame-accurate audio boundaries, you might do -c:a copy. But for “exact cuts”, re-encoding audio avoids weird edge cases (missing samples, bad timestamps, concat issues later).

===== Moves the MP4 “moov atom” to the beginning so the file can start playing before fully downloaded (web-friendly). =====
* Not required for local playback.
* It doesn’t change quality, only file layout.

==== You said: separate clips + millisecond precision if needed. ====

To cut with ms precision reliably, you generally need to decode and re-encode (at least video), because -c copy can only cut cleanly on keyframes and packet boundaries.

So the shortest “ms-accurate” version is basically:

<syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:01:02.000 -to 00:02:13.000 -c:v libx264 -c:a aac clip_01.mp4

</syntaxhighlight>

Everything else (-crf, -preset, -b:a, +faststart) is tuning / compatibility / convenience.

==== This is still ms-accurate for video (because it re-encodes video), and keeps audio untouched: ====

<syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:01:02.000 -to 00:02:13.000 -c:v libx264 -crf 20 -preset medium -c:a copy clip_01.mp4

</syntaxhighlight>

Caveat: if you later concatenate clips, audio-copy can sometimes make concat pickier depending on timestamps/codec parameters.

==== <syntaxhighlight lang="bash">ffmpeg -ss 00:01:02.000 -to 00:02:13.000 -i input.mp4 -c copy clip_01.mp4 ====

</syntaxhighlight>

Fast, no quality loss — but cuts may be off by up to a few seconds if keyframes are sparse.

If you tell me whether your priority is (1) perfect accuracy or (2) no re-encode / perfect quality, I’ll give you the best exact command for that.

=== User: i want to both preserve quality and be exact ===
i want to both preserve quality and be exact

=== Assistant: You can’t have both in the strict, literal sense unless your cut points land exactly on keyframes and audio packet boun… ===
You can’t have both in the strict, literal sense unless your cut points land exactly on keyframes (and audio packet boundaries). Reason: with -c copy ffmpeg is not allowed to invent new frames, so it can only start a clip on an existing keyframe; “millisecond exact” usually requires decoding frames and re-encoding the first GOP.

So you have two practical ways to get what you mean by “preserve quality”:

==== This is the only “no quality change” method: ====

<syntaxhighlight lang="bash">ffmpeg -ss 00:01:02.000 -to 00:02:13.000 -i input.mp4 -c copy clip_01.mp4

</syntaxhighlight>

But it will only be exact to the ms if there’s a keyframe exactly at 00:01:02.000 (rare).

==== You will re-encode, but you can make it lossless (or visually lossless). ====

===== Per clip: =====

<syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:01:02.000 -to 00:02:13.000 \
-c:v libx264 -qp 0 -preset veryslow \
-c:a copy \
clip_01_lossless.mkv

</syntaxhighlight>

Notes:
* -qp 0 = lossless for x264.
* I used MKV because it’s more forgiving; MP4 can be pickier with some codec combos.
* -c:a copy keeps audio unchanged.

===== <syntaxhighlight lang="bash">ffmpeg -i input.mp4 -ss 00:01:02.000 -to 00:02:13.000 \ =====
-c:v libx264 -crf 16 -preset slow \
-c:a copy \
clip_01.mkv

</syntaxhighlight>

(You can use CRF 14–18 depending on how paranoid you are.)

==== If you want the final clips to be -c copy and exact, you can first create a version that has keyframes exactly at your cut points: ====

===== <syntaxhighlight lang="bash">ffmpeg -i input.mp4 \ =====
-c:v libx264 -qp 0 -preset veryslow \
-force_key_frames "00:01:02.000,00:02:13.000,00:03:17.000,00:05:26.000,00:09:21.000,00:09:28.000,00:09:44.000,00:10:04.000" \
-c:a copy \
keyed.mkv

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -ss 00:01:02.000 -to 00:02:13.000 -i keyed.mkv -c copy clip_01.mkv =====
ffmpeg -ss 00:03:17.000 -to 00:05:26.000 -i keyed.mkv -c copy clip_02.mkv
ffmpeg -ss 00:09:21.000 -to 00:09:28.000 -i keyed.mkv -c copy clip_03.mkv
ffmpeg -ss 00:09:44.000 -to 00:10:04.000 -i keyed.mkv -c copy clip_04.mkv

</syntaxhighlight>

This still “changes” the video once (step 1), but with -qp 0 it’s lossless, so quality is preserved.

If you tell me your source codec/pix_fmt (paste ffprobe -hide_banner -i input.mp4), I can adjust for 10-bit / HDR, H.265, or ensure audio stays compatible with MP4 if you really need MP4 outputs.

=== User: here is the original video. ===
here is the original video. change your answer to fit its format/properties (in case any change does any improvement)

=== Assistant: Your source is: ===
Your source is:
* Container: MKV
* Video: H.264 High, 1920×1080, 30 fps, yuv420p, BT.709 / TV range
* Audio: Opus, 48 kHz, stereo

So the “best fit” output (same kind of file) is: MKV + H.264 + Opus, keeping 1080p/30fps/pix_fmt and BT.709 metadata.

Because you want exact cuts and “preserve quality”, the most faithful option is lossless H.264 re-encode (x264 -qp 0). That guarantees exact timestamps (ms) and no generation loss (but files can be bigger).

==== ### ====

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=62:end=133,setpts=PTS-STARTPTS[v];[0:a]atrim=start=62:end=133,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_01_0102-0213.mkv

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \ =====
"[0:v]trim=start=197:end=326,setpts=PTS-STARTPTS[v];[0:a]atrim=start=197:end=326,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_02_0317-0526.mkv

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \ =====
"[0:v]trim=start=561:end=568,setpts=PTS-STARTPTS[v];[0:a]atrim=start=561:end=568,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_03_0921-0928.mkv

</syntaxhighlight>

===== <syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \ =====
"[0:v]trim=start=584:end=604,setpts=PTS-STARTPTS[v];[0:a]atrim=start=584:end=604,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_04_0944-1004.mkv

</syntaxhighlight>

===== Just use decimals in the start= / end= values, e.g.: =====
* trim=start=197.237:end=326.041
* atrim=start=197.237:end=326.041

==== Same commands, just replace -qp 0 -preset veryslow with: ====
* Very high quality: -crf 16 -preset slow
* Still excellent: -crf 18 -preset slow

Example swap:

<syntaxhighlight lang="bash">-c:v libx264 -crf 16 -preset slow

</syntaxhighlight>

===== With MKV + Opus (and your file starting at -0.007s), trim/atrim + setpts/asetpts reliably: =====
* cuts exactly (including ms),
* resets each clip to start at t=0 cleanly,
* avoids weird negative start timestamps.

If you want, tell me one clip where you need ms precision (start/end), and I’ll plug those exact values into the command for you.

=== User: note that i still might need to cut up to miliseconds ===
note that i still might need to cut up to miliseconds

=== Assistant: Yep — the approach I gave still works fine with milliseconds. ===
Yep — the approach I gave still works fine with milliseconds. You just put decimals on the cut points.

===== You can do it either as seconds with decimals: =====
* start=62.137:end=133.904

or as HH:MM:SS.mmm (ffmpeg accepts this format too, but inside trim it’s simplest to use seconds).

===== Say you decide clip 2 should be 03:17.237 → 05:26.041. =====

03:17.237 = 197.237 seconds
05:26.041 = 326.041 seconds

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=197.237:end=326.041,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=197.237:end=326.041,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_02_0317p237-0526p041.mkv

</syntaxhighlight>

===== Your video is 30 fps, so frames are spaced about 33.333 ms apart. =====
That means:
* You can type millisecond timestamps,
* but the actual video cut can only land on a frame boundary (≈33ms steps).
* Audio can be trimmed much more finely (sample-level).

If you want, paste the exact ms cut points you end up with (like 01:02.153–02:13.087) and I’ll rewrite all 4 commands with those exact values.

=== User: first one is 01:02.2 till 02:13.2 ===
first one is 01:02.2 till 02:13.2

=== Assistant: Cool — for clip 1 you want 00:01:02.200 → 00:02:13.200 i.e. ===
Cool — for clip 1 you want 00:01:02.200 → 00:02:13.200 (i.e. 62.2s → 133.2s).

===== <syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \ =====
"[0:v]trim=start=62.2:end=133.2,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=62.2:end=133.2,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_01_0102p2-0213p2.mkv

</syntaxhighlight>

Quick note: your video is 30 fps, so the video cut will land on the nearest frame boundary (~33.3 ms steps). Audio can still be trimmed more finely.

=== User: $ ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM P9gZEDOz9eE.mkv" -filtercomplex \ ===
$ ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=62.2:end=133.2,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=62.2:end=133.2,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -profile:v high -level 4.0 \
-color_range tv -colorspace bt709 -color_trc bt709 -color_primaries bt709 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_01_0102p2-0213p2.mkv
ffmpeg version 4.4.2-0ubuntu0.22.04.1 Copyright (c) 2000-2021 the FFmpeg developers
built with gcc 11 (Ubuntu 11.2.0-19ubuntu1)
configuration: --prefix=/usr --extra-version=0ubuntu0.22.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-librsvg --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
WARNING: library configuration mismatch
avcodec configuration: --prefix=/usr --extra-version=0ubuntu0.22.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libdav1d --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librabbitmq --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzimg --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-pocketsphinx --enable-librsvg --enable-libmfx --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared --enable-version3 --disable-doc --disable-programs --enable-libaribb24 --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libtesseract --enable-libvo_amrwbenc --enable-libsmbclient
libavutil 56. 70.100 / 56. 70.100
libavcodec 58.134.100 / 58.134.100
libavformat 58. 76.100 / 58. 76.100
libavdevice 58. 13.100 / 58. 13.100
libavfilter 7.110.100 / 7.110.100
libswscale 5. 9.100 / 5. 9.100
libswresample 3. 9.100 / 3. 9.100
libpostproc 55. 9.100 / 55. 9.100
Input #0, matroska,webm, from 'NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv':
Metadata:
COMPATIBLE_BRANDS: iso6avc1mp41
MAJOR_BRAND : dash
MINOR_VERSION : 0
ENCODER : Lavf58.76.100
Duration: 00:25:49.28, start: -0.007000, bitrate: 2264 kb/s
Stream #0:0: Video: h264 (High), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 30 fps, 30 tbr, 1k tbn, 60 tbc (default)
Metadata:
HANDLER_NAME : ISO Media file produced by Google Inc.
VENDOR_ID : [0][0][0][0]
DURATION : 00:25:49.266000000
Stream #0:1(eng): Audio: opus, 48000 Hz, stereo, fltp (default)
Metadata:
DURATION : 00:25:49.281000000
Stream mapping:
Stream #0:0 (h264) -> trim
Stream #0:1 (opus) -> atrim
setpts -> Stream #0:0 (libx264)
asetpts -> Stream #0:1 (libopus)
Press [q] to stop, [?] for help
x264 [error]: high profile doesn't support lossless
[libx264 @ 0x5874e72a1640] Error setting profile high.
[libx264 @ 0x5874e72a1640] Possible profiles: baseline main high high10 high422 high444
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
[libopus @ 0x5874e739cb80] 1 frames left in the queue on closing
Conversion failed!

=== Assistant: That error is because of this combo: ===
That error is because of this combo:
* -qp 0 = lossless
* -profile:v high = forces “High” profile

x264 refuses that: “high profile doesn't support lossless”. For lossless, x264 switches to a different profile (typically High 4:4:4 Predictive) automatically. When you force high, it can’t.

===== Use this: =====

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=62.2:end=133.2,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=62.2:end=133.2,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_01_0102p2-0213p2.mkv

</syntaxhighlight>

That will cut exactly (including milliseconds) and keep video lossless.

===== Even though your pixel format stays yuv420p, a lossless x264 encode often signals a profile like High 4:4:4 Predictive. Some hardware players (TVs/phones) may not like that, even if VLC/mpv do. =====

If you want maximum compatibility while still being visually indistinguishable from the source, do this instead:

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=62.2:end=133.2,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=62.2:end=133.2,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -crf 16 -preset slow -pix_fmt yuv420p -profile:v high -level 4.0 \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_01_0102p2-0213p2.mkv

</syntaxhighlight>

===== Just change 62.2 / 133.2 to e.g. 62.237 / 133.041. =====

If you send the ms-precise times for the other 3 clips, I’ll spit out all 4 final commands in the same style.

=== User: second is 03:17.10 to 05:26.20 ===
second is 03:17.10 to 05:26.20

=== Assistant: Great — that’s: ===
Great — that’s:
* start 00:03:17.100 = 197.1 seconds
* end 00:05:26.200 = 326.2 seconds

Here’s the matching command (same settings as the fixed lossless version — no forced -profile:v high):

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=197.1:end=326.2,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=197.1:end=326.2,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_02_0317p10-0526p20.mkv

</syntaxhighlight>

If you want the filename to reflect milliseconds more clearly, you can rename it after (or I can format it differently).

Send clip 3 + 4 ms times when ready.

=== User: 09:21:00 till 09:28:30 ===
09:21:00 till 09:28:30

=== Assistant: That’s: ===
That’s:
* start 00:09:21.000 = 561.0 seconds
* end 00:09:28.300 = 568.3 seconds

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=561.0:end=568.3,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=561.0:end=568.3,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_03_0921p00-0928p30.mkv

</syntaxhighlight>

Send the last interval (09:44–10:04 with ms) and I’ll format that one too.

=== User: 09:44:10 to 10:04:20 ===
09:44:10 to 10:04:20

=== Assistant: That’s: ===
That’s:
* start 00:09:44.100 = 584.1 seconds
* end 00:10:04.200 = 604.2 seconds

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=584.1:end=604.2,setpts=PTS-STARTPTS[v]; \
[0:a]atrim=start=584.1:end=604.2,asetpts=PTS-STARTPTS[a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
clip_04_0944p10-1004p20.mkv

</syntaxhighlight>

If you want, here are all four commands together (same settings) so you can paste once:

<syntaxhighlight lang="bash">in="NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv"

ffmpeg -i "$in" -filter_complex "[0:v]trim=start=62.2:end=133.2,setpts=PTS-STARTPTS[v];[0:a]atrim=start=62.2:end=133.2,asetpts=PTS-STARTPTS[a]" -map "[v]" -map "[a]" -c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -c:a libopus -b:a 160k -ar 48000 -ac 2 clip_01_0102p20-0213p20.mkv
ffmpeg -i "$in" -filter_complex "[0:v]trim=start=197.1:end=326.2,setpts=PTS-STARTPTS[v];[0:a]atrim=start=197.1:end=326.2,asetpts=PTS-STARTPTS[a]" -map "[v]" -map "[a]" -c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -c:a libopus -b:a 160k -ar 48000 -ac 2 clip_02_0317p10-0526p20.mkv
ffmpeg -i "$in" -filter_complex "[0:v]trim=start=561.0:end=568.3,setpts=PTS-STARTPTS[v];[0:a]atrim=start=561.0:end=568.3,asetpts=PTS-STARTPTS[a]" -map "[v]" -map "[a]" -c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -c:a libopus -b:a 160k -ar 48000 -ac 2 clip_03_0921p00-0928p30.mkv
ffmpeg -i "$in" -filter_complex "[0:v]trim=start=584.1:end=604.2,setpts=PTS-STARTPTS[v];[0:a]atrim=start=584.1:end=604.2,asetpts=PTS-STARTPTS[a]" -map "[v]" -map "[a]" -c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p -c:a libopus -b:a 160k -ar 48000 -ac 2 clip_04_0944p10-1004p20.mkv

</syntaxhighlight>

=== User: ok, now in a single ffmpeg command create the combined video of the cuts ===
ok, now in a single ffmpeg command create the combined video of the cuts

=== Assistant: Here’s a single ffmpeg command that cuts your 4 timestamp ranges with milliseconds and concats them into one output. ===
Here’s a single ffmpeg command that cuts your 4 timestamp ranges (with milliseconds) and concats them into one output.

===== Combined output (exact cuts, lossless video, MKV + H.264 + Opus) =====

<syntaxhighlight lang="bash">ffmpeg -i "NEA MADALIN E DRAG QUEEN ACUM [P9gZEDOz9eE].mkv" -filter_complex \
"[0:v]trim=start=62.2:end=133.2,setpts=PTS-STARTPTS[v0]; \
[0:a]atrim=start=62.2:end=133.2,asetpts=PTS-STARTPTS[a0]; \
[0:v]trim=start=197.1:end=326.2,setpts=PTS-STARTPTS[v1]; \
[0:a]atrim=start=197.1:end=326.2,asetpts=PTS-STARTPTS[a1]; \
[0:v]trim=start=561.0:end=568.3,setpts=PTS-STARTPTS[v2]; \
[0:a]atrim=start=561.0:end=568.3,asetpts=PTS-STARTPTS[a2]; \
[0:v]trim=start=584.1:end=604.2,setpts=PTS-STARTPTS[v3]; \
[0:a]atrim=start=584.1:end=604.2,asetpts=PTS-STARTPTS[a3]; \
[v0][a0][v1][a1][v2][a2][v3][a3]concat=n=4:v=1:a=1[v][a]" \
-map "[v]" -map "[a]" \
-c:v libx264 -preset veryslow -qp 0 -pix_fmt yuv420p \
-c:a libopus -b:a 160k -ar 48000 -ac 2 \
combined_cuts.mkv

</syntaxhighlight>

If you decide “lossless” is overkill and you want maximum playback compatibility (High profile) while still looking identical to most eyes, swap the video settings to:

<syntaxhighlight lang="bash">-c:v libx264 -crf 16 -preset slow -pix_fmt yuv420p -profile:v high -level 4.0

</syntaxhighlight>

(Everything else can stay the same.)

=== User: how much will be duration of the new video? ===
how much will be duration of the new video?

=== Assistant: Let’s add up each kept segment: ===
Let’s add up each kept segment:
# 01:02.200 → 02:13.200 133.2 − 62.2 = 71.0 s
# 03:17.100 → 05:26.200 326.2 − 197.1 = 129.1 s
# 09:21.000 → 09:28.300 568.3 − 561.0 = 7.3 s
# 09:44.100 → 10:04.200 604.2 − 584.1 = 20.1 s

Total = 71.0 + 129.1 + 7.3 + 20.1 = 227.5 seconds
= 3 minutes 47.5 seconds (i.e., 00:03:47.500)

=== User: do cummulative sum and also convert into minutes so i can see where the cuts are of the total ===
do cummulative sum (and also convert into minutes) so i can see where the cuts are of the total

=== Assistant: Sure — here are the segment lengths and the cumulative timeline in the new combined video. ===
Sure — here are the segment lengths and the cumulative timeline in the new combined video.

===== Segment durations =====
* S1 (01:02.200 → 02:13.200): 71.000 s = 1.1833 min = 01:11.000
* S2 (03:17.100 → 05:26.200): 129.100 s = 2.1517 min = 02:09.100
* S3 (09:21.000 → 09:28.300): 7.300 s = 0.1217 min = 00:07.300
* S4 (09:44.100 → 10:04.200): 20.100 s = 0.3350 min = 00:20.100

===== Cumulative positions in the combined output =====

| Segment | In source | Duration | Starts at (new) | Ends at (new) | End (minutes) |
| ------- | ------------------- | --------- | --------------- | ------------- | ------------- |
| S1 | 01:02.200–02:13.200 | 71.000 s | 00:00.000 | 01:11.000 | 1.1833 min |
| S2 | 03:17.100–05:26.200 | 129.100 s | 01:11.000 | 03:20.100 | 3.3350 min |
| S3 | 09:21.000–09:28.300 | 7.300 s | 03:20.100 | 03:27.400 | 3.4567 min |
| S4 | 09:44.100–10:04.200 | 20.100 s | 03:27.400 | 03:47.500 | 3.7917 min |

Total combined duration: 227.500 s = 3.7917 min = 03:47.500

=== User: make the table ascii only ===
make the table ascii only

=== Assistant: ===
<syntaxhighlight>+---------+-------------------------+-----------+----------------+----------------+-------------+
| Segment | In source | Duration | Starts at (new) | Ends at (new) | End (min) |
+---------+-------------------------+-----------+----------------+----------------+-------------+
| S1 | 01:02.200 - 02:13.200 | 01:11.000 | 00:00.000 | 01:11.000 | 1.1833 min |
| S2 | 03:17.100 - 05:26.200 | 02:09.100 | 01:11.000 | 03:20.100 | 3.3350 min |
| S3 | 09:21.000 - 09:28.300 | 00:07.300 | 03:20.100 | 03:27.400 | 3.4567 min |
| S4 | 09:44.100 - 10:04.200 | 00:20.100 | 03:27.400 | 03:47.500 | 3.7917 min |
+---------+-------------------------+-----------+----------------+----------------+-------------+
| TOTAL | | 03:47.500 | | | 3.7917 min |
+---------+-------------------------+-----------+----------------+----------------+-------------+

</syntaxhighlight>

== References ==
<references />

[[Category:ChatGPT Shares]]
[[Category:openai]]

Openai/6957d2e8-b738-8008-987a-09a5d9f29bc8 - Revision history

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