Hi, When re-wrapping DPX or TIFF images to Matroska, it appears that FFmpeg uses the V_QUICKTIME codec ID. Why is this used? Would something like V_UNCOMPRESSED (for raw TIFF anyhow) b more appropriate/
The reason why I'm investigating this is that DPC and TIFF rewrappings to Matroska appear to be fully reversible with matching whole-file checksums. To replicate using ffmpeg and mediainfo: $ ./ffmpeg -f lavfi -i testsrc -c:v tiff -compression_algo raw -y -t 1 1_tiff.mkv && mediainfo --Details=1 1_tiff.mkv|grep -i codec ffmpeg version N-92521-g737b5f5869 Copyright (c) 2000-2018 the FFmpeg developers built with gcc 7 (Ubuntu 7.3.0-27ubuntu1~18.04) configuration: libavutil 56. 24.101 / 56. 24.101 libavcodec 58. 40.100 / 58. 40.100 libavformat 58. 23.100 / 58. 23.100 libavdevice 58. 6.100 / 58. 6.100 libavfilter 7. 46.100 / 7. 46.100 libswscale 5. 4.100 / 5. 4.100 libswresample 3. 4.100 / 3. 4.100 Input #0, lavfi, from 'testsrc': Duration: N/A, start: 0.000000, bitrate: N/A Stream #0:0: Video: rawvideo (RGB[24] / 0x18424752), rgb24, 320x240 [SAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc Stream mapping: Stream #0:0 -> #0:0 (rawvideo (native) -> tiff (native)) Press [q] to stop, [?] for help Output #0, matroska, to '1_tiff.mkv': Metadata: encoder : Lavf58.23.100 Stream #0:0: Video: tiff (tiff / 0x66666974), rgb24, 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 25 fps, 1k tbn, 25 tbc Metadata: encoder : Lavc58.40.100 tiff frame= 25 fps=0.0 q=-0.0 Lsize= 5638kB time=00:00:00.96 bitrate=48061.9kbits/s speed=58.3x video:5636kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.034428% 0001AE CodecID - V_QUICKTIME (13 bytes) 0001CB CodecPrivate (93 bytes) $ ./ffmpeg -f lavfi -i testsrc -c:v dpx -y -t 1 1_dpx.mkv && mediainfo --Details=1 1_tiff.mkv|grep -i codec ffmpeg version N-92521-g737b5f5869 Copyright (c) 2000-2018 the FFmpeg developers built with gcc 7 (Ubuntu 7.3.0-27ubuntu1~18.04) configuration: libavutil 56. 24.101 / 56. 24.101 libavcodec 58. 40.100 / 58. 40.100 libavformat 58. 23.100 / 58. 23.100 libavdevice 58. 6.100 / 58. 6.100 libavfilter 7. 46.100 / 7. 46.100 libswscale 5. 4.100 / 5. 4.100 libswresample 3. 4.100 / 3. 4.100 Input #0, lavfi, from 'testsrc': Duration: N/A, start: 0.000000, bitrate: N/A Stream #0:0: Video: rawvideo (RGB[24] / 0x18424752), rgb24, 320x240 [SAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc Stream mapping: Stream #0:0 -> #0:0 (rawvideo (native) -> dpx (native)) Press [q] to stop, [?] for help Output #0, matroska, to '1_dpx.mkv': Metadata: encoder : Lavf58.23.100 Stream #0:0: Video: dpx (dpx / 0x20787064), rgb24, 320x240 [SAR 1:1 DAR 4:3], q=2-31, 200 kb/s, 25 fps, 1k tbn, 25 tbc Metadata: encoder : Lavc58.40.100 dpx frame= 25 fps=0.0 q=-0.0 Lsize= 5668kB time=00:00:00.96 bitrate=48312.5kbits/s speed=57.6x video:5666kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.033439% 0001AE CodecID - V_QUICKTIME (13 bytes) 0001CB CodecPrivate (93 bytes) _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".