-----Original Message----- From: ffmpeg-user <ffmpeg-user-boun...@ffmpeg.org> On Behalf Of Paul B Mahol Sent: Wednesday, June 18, 2025 4:25 PM To: FFmpeg user questions <ffmpeg-user@ffmpeg.org> Subject: Re: [FFmpeg-user] Yes or No? About the processing pipeline.
On Tue, Jun 17, 2025 at 11:19 PM Mark Filipak < markfilipak.imdb-at-gmail....@ffmpeg.org> wrote: > On 17/06/2025 12.50, Paul B Mahol wrote: > > On Tue, Jun 17, 2025 at 4:18 PM Mark Filipak < > > markfilipak.imdb-at-gmail....@ffmpeg.org> wrote: > > > >> Yes (true) or No (false)? > >> > >> If the input is 8-bit ybr420-smpte170m, then the processing pipeline is > >> also 8-bit ybr420-smpte170m. > > > > There is no such thing like ybr420. > > You know what? You're right! Ha, ha, ha! > > When I read Jim DeLaHunt's treatise on framing and saw "rgb420" in it, I > thought "Huh"? > > I apologize for the error, Paul. I started with a statement about ybr420 > and got sidetracked when I > succumbed to an impulse to add a second (bogus) example. I sabotaged > myself. > > I do apologize. > > Maybe you can tell me why this experiment fails. > > ffmpeg^ > -i "c:\8-bit ybr420 smpte170m.mkv"^ > -map 0 -c:v libx264 -c:a copy^ > "c:\8-bit ybr420 smpte170m.mp4" > > ffmpeg version N-119869-g3ac7d70291-20250611 Copyright (c) 2000-2025 the > FFmpeg developers > built with gcc 15.1.0 (crosstool-NG 1.27.0.42_35c1e72) > configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static > --pkg-config=pkg-config > --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 > --enable-gpl --enable-version3 > --disable-debug --enable-shared --disable-static --disable-w32threads > --enable-pthreads > --enable-iconv --enable-zlib --enable-libfribidi --enable-gmp > --enable-libxml2 --enable-lzma > --enable-fontconfig --enable-libharfbuzz --enable-libfreetype > --enable-libvorbis --enable-opencl > --disable-libpulse --enable-libvmaf --disable-libxcb --disable-xlib > --enable-amf --enable-libaom > --enable-libaribb24 --enable-avisynth --enable-chromaprint > --enable-libdav1d --enable-libdavs2 > --enable-libdvdread --enable-libdvdnav --disable-libfdk-aac > --enable-ffnvcodec --enable-cuda-llvm > --enable-frei0r --enable-libgme --enable-libkvazaar > --enable-libaribcaption --enable-libass > --enable-libbluray --enable-libjxl --enable-libmp3lame --enable-libopus > --enable-librist > --enable-libssh --enable-libtheora --enable-libvpx --enable-libwebp > --enable-libzmq --enable-lv2 > --enable-libvpl --enable-openal --enable-liboapv > --enable-libopencore-amrnb > --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg > --enable-libopenmpt > --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 > --enable-libsnappy > --enable-libsoxr --enable-libsrt --enable-libsvtav1 --enable-libtwolame > --enable-libuavs3d > --disable-libdrm --enable-vaapi --enable-libvidstab --enable-vulkan > --enable-libshaderc > --enable-libplacebo --enable-libvvenc --enable-libx264 --enable-libx265 > --enable-libxavs2 > --enable-libxvid --enable-libzimg --enable-libzvbi > --extra-cflags=-DLIBTWOLAME_STATIC > --extra-cxxflags= --extra-libs=-lgomp --extra-ldflags=-pthread > --extra-ldexeflags= > --cc=x86_64-w64-mingw32-gcc --cxx=x86_64-w64-mingw32-g++ > --ar=x86_64-w64-mingw32-gcc-ar > --ranlib=x86_64-w64-mingw32-gcc-ranlib --nm=x86_64-w64-mingw32-gcc-nm > --extra-version=20250611 > libavutil 60. 3.100 / 60. 3.100 > libavcodec 62. 3.101 / 62. 3.101 > libavformat 62. 1.100 / 62. 1.100 > libavdevice 62. 0.100 / 62. 0.100 > libavfilter 11. 0.100 / 11. 0.100 > libswscale 9. 0.100 / 9. 0.100 > libswresample 6. 0.100 / 6. 0.100 > Input #0, matroska,webm, from 'c:\8-bit ybr420 smpte170m.mkv': > Metadata: > creation_time : 2025-06-15T04:54:18.000000Z > ENCODER : Lavf58.29.100 > Duration: 01:59:25.20, start: 0.000000, bitrate: 666 kb/s > Stream #0:0: Video: mpeg2video (Main), yuv420p(tv, smpte170m, > progressive), 720x480 [SAR 32:27 > DAR 16:9], 23.98 fps, 23.98 tbr, 1k tbn (default) > Metadata: > DURATION : 01:59:25.200000000 > Side data: > cpb: bitrate max/min/avg: 0/0/0 buffer size: 49152 vbv_delay: N/A > Stream #0:1: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s, Start > 0.004000 (default) > Metadata: > title : Surround > DURATION : 01:59:25.188000000 > Stream #0:2: Subtitle: dvd_subtitle (dvdsub), 720x480 > Metadata: > DURATION : 01:52:11.916000000 > [sost#0:2 @ 0000000004c5ec80] Automatic encoder selection failed Default > encoder for format mp4 > (codec none) is probably disabled. Please choose an encoder manually. > > You need to select video encoder manually because it failed to pick one for > you automatically. > [sost#0:2 @ 0000000004c5ec80] Error selecting an encoder > Error opening output file c:\8-bit ybr420 smpte170m.mp4. > Error opening output files: Encoder not found Well, > ffmpeg^ > -i "c:\8-bit ybr420 smpte170m.mkv"^ > -map 0 -c:v libx264 -c:a copy^ > "c:\8-bit ybr420 smpte170m.mp4" Perhaps no subtitle encoder specified ? ChatGPT says: > The FFmpeg option -map 0 is used to explicitly include all streams (video, > audio, subtitles, metadata, etc.) from the first input file (index 0) in the > output. > What does -map 0 mean exactly? > -map 0 says: > Include all streams from the first input (0) in the output. > This includes: > All video streams > All audio streams > All subtitle streams > Any data or attachment streams > Even chapters and metadata And your log seems to indicate subtitles are present. Just a thought, I am likely wrong. _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
