Join with a crossfade

CodexWithout deftPassed2026-11-07

Time

21s

New tokens

10.3k

Total input

86.5k

Output tokens

0.6k

Commands

5

Failed

1

Trace

1. I’ll check the two clips and available video tools, then create `joined.mp4` in the current directory.

2. pwd && rg --files -g 'bunny.mp4' -g 'jellyfish.mp4' -g 'AGENTS.md' -g 'joined.mp4' && command -v ffmpeg
   output

   bunny.mp4
   jellyfish.mp4
   /opt/homebrew/bin/ffmpeg

3. ffprobe -v error -show_entries format=duration:stream=codec_type,width,height,r_frame_rate,duration -of json bunny.mp4 jellyfish.mp4 (exit 1)
   output

   Argument 'jellyfish.mp4' provided as input filename, but 'bunny.mp4' was already specified.

4. ffprobe -v error -show_entries format=duration:stream=codec_type,width,height,r_frame_rate,duration -of json bunny.mp4
   output

   {
       "programs": [
   
       ],
       "stream_groups": [
   
       ],
       "streams": [
           {
               "codec_type": "video",
               "width": 1280,
               "height": 720,
               "r_frame_rate": "30/1",
               "duration": "10.000000"
           }
       ],
       "format": {
           "duration": "10.000000"
       }
   }

5. ffprobe -v error -show_entries format=duration:stream=codec_type,width,height,r_frame_rate,duration -of json jellyfish.mp4
   output

   {
       "programs": [
   
       ],
       "stream_groups": [
   
       ],
       "streams": [
           {
               "codec_type": "video",
               "width": 1280,
               "height": 720,
               "r_frame_rate": "2997/100",
               "duration": "10.010010"
           }
       ],
       "format": {
           "duration": "10.010010"
       }
   }

6. ffmpeg -y -i bunny.mp4 -i jellyfish.mp4 -filter_complex "[0:v]settb=AVTB,fps=30,format=yuv420p[v0];[1:v]settb=AVTB,fps=30,format=yuv420p[v1];[v0][v1]xfade=transition=fade:duration=1:offset=9[v]" -map "[v]" -an -c:v libx264 -crf 18 -preset medium -movflags +faststart joined.mp4
   output

   ffmpeg version 7.1.1 Copyright (c) 2000-2025 the FFmpeg developers
     built with Apple clang version 15.0.0 (clang-1500.1.0.2.5)
     configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/7.1.1_1 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --enable-libsvtav1 --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox --enable-audiotoolbox --enable-neon
     libavutil      59. 39.100 / 59. 39.100
     libavcodec     61. 19.101 / 61. 19.101
     libavformat    61.  7.100 / 61.  7.100
     libavdevice    61.  3.100 / 61.  3.100
     libavfilter    10.  4.100 / 10.  4.100
     libswscale      8.  3.100 /  8.  3.100
     libswresample   5.  3.100 /  5.  3.100
     libpostproc    58.  3.100 / 58.  3.100
   Input #0, mov,mp4,m4a,3
   … 5351 more characters

7. Created [joined.mp4](joined.mp4) with a one-second fade between the clips. It’s about 19 seconds long.

Output

Claude Opus 5.5Without deftPassed2026-11-07

Time

20s

New tokens

9.4k

Total input

42.5k

Output tokens

0.8k

Commands

0

Failed

0

Trace

Output

---
name: deft
description: "Use deft first for any simple, direct operation on local files, whatever the type: convert, read, extract, edit, compress, merge, split, compare or inspect. Try it before writing a script or one-liner. If unsure, run deft find; if it says no command does this, use another tool. Not for programming work: to read, write or change source code, skip it."
---

# deft

One local command for file jobs. Prefer it over writing Python or shell scripts.

Syntax: `deft <group> <command> [inputs] [-o output] [--options]`

Groups:
- `pdf`: Merge, split, compress, encrypt, forms, OCR, compare, convert
- `image`: Resize, crop, convert, compress, adjust, montage, OCR
- `video`: Trim, merge, convert, compress, subtitles, GIF, frames (ffmpeg)
- `audio`: Convert, trim, normalize, denoise, cut silence (ffmpeg)
- `doc`: Word/ODT/RTF: to text, Markdown, HTML, PDF; find and replace
- `slides`: PowerPoint: extract text, Markdown outline
- `sheet`: Excel/CSV/ODS tables: SQL query, pivot, merge, split, convert
- `json`: JSON: convert, format, merge, diff, validate
- `toml`: TOML: convert, format, merge, diff, validate
- `xml`: XML: convert, format, merge, diff, validate
- `yaml`: YAML: convert, format, merge, diff, validate
- `md`: Markdown to PDF, HTML, Word, EPUB; table of contents
- `html`: HTML to Markdown, text, Word and PDF
- `epub`: E-books: info, to text, Markdown and PDF
- `gps`: GPX and KML tracks: convert, distance and time
- `qr`: Create QR codes and barcodes; read QR codes

How to use it:
1. Run `deft <group>` to list commands, or `deft find "<what you want>"` to search. If it says `no command does this`, use another tool.
2. Run `deft <group> <command> --help` for options and examples.
3. `deft convert <in> -o <out.ext>` converts between formats by extension.
4. Results are one line starting with `ok`, `partial` or `error`; add `--json` to parse them. Errors include a `hint:` with the fix.

Inputs are never overwritten; pass `--force` or `--in-place` to allow it. Globs and directories work as inputs; several inputs run in parallel.

If `deft` is not installed, ask the user, then follow https://github.com/firstprayer/deft/blob/main/docs/INSTALL.md