#7058: loud aac encoder artefact -------------------------------------+------------------------------------- Reporter: nol2ter | Owner: Type: defect | Status: new Priority: important | Component: avcodec Version: git-master | Resolution: Keywords: aac | Blocked By: regression | Reproduced by developer: 0 Blocking: | Analyzed by developer: 0 | -------------------------------------+------------------------------------- Changes (by cehoyos):
* keywords: => aac regression * priority: normal => important * version: unspecified => git-master * component: undetermined => avcodec Comment: Strangest bug ever, thank you! I believe this is a regression since 8005b6de4f88c9e3739a3a4ceda4288804788df9 For the original command line, the bug depends on `strlen(LIBAVCODEC_IDENT)`, explaining why it was a regression since 70143a3954e1c4412efb2bf1a3a818adea2d3abf fixed by 36c85d6e773d51af1d084fb15ad89d9acc5dd893 but the issue is also reproducible without writing bitstream info: {{{ $ ffmpeg -i 59s_sound_falls_original.flac -b:a 320k -flags +bitexact -aac_coder twoloop -t 65 out.aac ffmpeg version N-90232-g0645698 Copyright (c) 2000-2018 the FFmpeg developers built with gcc 6.3.0 (GCC) configuration: --enable-gpl libavutil 56. 8.100 / 56. 8.100 libavcodec 58. 13.102 / 58. 13.102 libavformat 58. 10.100 / 58. 10.100 libavdevice 58. 2.100 / 58. 2.100 libavfilter 7. 12.100 / 7. 12.100 libswscale 5. 0.102 / 5. 0.102 libswresample 3. 0.101 / 3. 0.101 libpostproc 55. 0.100 / 55. 0.100 Input #0, flac, from '59s_sound_falls_original.flac': Metadata: TITLE : Clarity ARTIST : Zedd, Foxes ALBUMTITLE : Clarity COMMENT : 00602537547067_1_5;0bfaa24dc0cb300acd9f604b3b5f261b Duration: 00:04:31.43, start: 0.000000, bitrate: 1046 kb/s Stream #0:0: Audio: flac, 44100 Hz, stereo, s16 Stream mapping: Stream #0:0 -> #0:0 (flac (native) -> aac (native)) Press [q] to stop, [?] for help [adts @ 0x27d3140] The AVFormatContext is not in set to bitexact mode, only the AVCodecContext. If this is not intended, set AVFormatContext.flags |= AVFMT_FLAG_BITEXACT. Output #0, adts, to 'out.aac': Metadata: TITLE : Clarity ARTIST : Zedd, Foxes ALBUMTITLE : Clarity COMMENT : 00602537547067_1_5;0bfaa24dc0cb300acd9f604b3b5f261b encoder : Lavf58.10.100 Stream #0:0: Audio: aac (LC), 44100 Hz, stereo, fltp (16 bit), 320 kb/s Metadata: encoder : Lavc aac size= 2534kB time=00:01:05.01 bitrate= 319.3kbits/s speed=19.4x video:0kB audio:2515kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.761414% [aac @ 0x27d42c0] Qavg: 9635.397 }}} The output file contains a very audible artefact after 59 seconds. -- Ticket URL: <https://trac.ffmpeg.org/ticket/7058#comment:3> FFmpeg <https://ffmpeg.org> FFmpeg issue tracker _______________________________________________ FFmpeg-trac mailing list FFmpeg-trac@avcodec.org http://ffmpeg.org/mailman/listinfo/ffmpeg-trac