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Bug de détection d’ogg
22 mars 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Video
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FFMPEG Unable to Decode Quicktime QDMC Stream (No decoder for stream)
9 janvier 2017, par mbmastWe are using FFMPEG to convert iPhone video to MP4. This requires an AAC decoder which is not included in any binary distributions of FFMPEG (due to licensing issues). The solution is to download the FFMPEG source and compile it yourself. I’ve done this, apparently incorrectly, as I cannot decode the audio stream. I am getting this error :
/usr/ffmpeg_builds/ffmpeg -y -i /home/domain/public_html/wp-content/uploads/celebs/main/step-2.mov -threads 12 -vcodec libx264 -acodec libfdk_aac -b:v 1000k -refs 6 -coder 1 -sc_threshold 40 -flags +loop -me_range 16 -subq 7 -i_qfactor 0.71 -qcomp 0.6 -qdiff 4 -trellis 1 -b:a 128k -pass 1 -passlogfile /tmp/ffmpeg-passes57a054ee917c4ahl3t/pass-57a054ee91965 /home/domain/public_html/wp-content/uploads/celebs/main/testing-5.mp4
ffmpeg version N-81827-g81bab10 Copyright (c) 2000-2016 the FFmpeg developers
built with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-17)
configuration: --prefix=/root/ffmpeg_build --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --pkg-config-flags=--static --enable-gpl --enable-nonfree --enable-libfdk-aac --enable-libfreetype --enable-libx264
libavutil 55. 32.100 / 55. 32.100
libavcodec 57. 60.100 / 57. 60.100
libavformat 57. 51.102 / 57. 51.102
libavdevice 57. 0.102 / 57. 0.102
libavfilter 6. 63.100 / 6. 63.100
libswscale 4. 1.100 / 4. 1.100
libswresample 2. 2.100 / 2. 2.100
libpostproc 54. 0.100 / 54. 0.100
Guessed Channel Layout for Input Stream #0.1 : mono
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/domain/public_html/wp-content/uploads/celebs/main/step-2.mov':
Metadata:
creation_time : 1998-11-04T16:40:13.000000Z
Duration: 00:01:00.83, start: 0.000000, bitrate: 110 kb/s
Stream #0:0(eng): Video: svq1 (SVQ1 / 0x31515653), yuv410p, 160x120, 90 kb/s, 7.51 fps, 7.50 tbr, 600 tbn, 600 tbc (default)
Metadata:
creation_time : 1998-11-04T16:40:13.000000Z
handler_name : Apple Alias Data Handler
encoder : Sorenson Video
Stream #0:1(eng): Audio: qdmc (QDMC / 0x434D4451), 44100 Hz, mono (default)
Metadata:
creation_time : 1998-11-04T16:40:13.000000Z
handler_name : Apple Alias Data Handler
No decoder for stream #0:1, filtering impossible
Error opening filters!I suspect that I failed to compile and include the correct codec library when I built FFMPEG. The problem is I don’t know which library I should have built/included. I haven’t found anything that says to decode QDMC audio in FFMPEG you need the XXXXX library.
Here’s the complete list of decoders that my build supports :
/usr/ffmpeg_builds/ffmpeg -decoders
ffmpeg version N-81827-g81bab10 Copyright (c) 2000-2016 the FFmpeg developers
built with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-17)
configuration: --prefix=/root/ffmpeg_build --extra-cflags=-I/root/ffmpeg_build/include --extra-ldflags=-L/root/ffmpeg_build/lib --bindir=/root/bin --pkg-config-flags=--static --enable-gpl --enable-nonfree --enable-libfdk-aac --enable-libfreetype --enable-libx264
libavutil 55. 32.100 / 55. 32.100
libavcodec 57. 60.100 / 57. 60.100
libavformat 57. 51.102 / 57. 51.102
libavdevice 57. 0.102 / 57. 0.102
libavfilter 6. 63.100 / 6. 63.100
libswscale 4. 1.100 / 4. 1.100
libswresample 2. 2.100 / 2. 2.100
libpostproc 54. 0.100 / 54. 0.100
Decoders:
V..... = Video
A..... = Audio
S..... = Subtitle
.F.... = Frame-level multithreading
..S... = Slice-level multithreading
...X.. = Codec is experimental
....B. = Supports draw_horiz_band
.....D = Supports direct rendering method 1
------
V....D 012v Uncompressed 4:2:2 10-bit
V....D 4xm 4X Movie
V....D 8bps QuickTime 8BPS video
V....D aasc Autodesk RLE
VF...D aic Apple Intermediate Codec
V....D alias_pix Alias/Wavefront PIX image
V....D amv AMV Video
V....D anm Deluxe Paint Animation
V....D ansi ASCII/ANSI art
VF...D apng APNG (Animated Portable Network Graphics) image
V....D asv1 ASUS V1
V....D asv2 ASUS V2
V....D aura Auravision AURA
V....D aura2 Auravision Aura 2
V....D avrn Avid AVI Codec
V....D avrp Avid 1:1 10-bit RGB Packer
V....D avs AVS (Audio Video Standard) video
V....D avui Avid Meridien Uncompressed
V....D ayuv Uncompressed packed MS 4:4:4:4
V....D bethsoftvid Bethesda VID video
V....D bfi Brute Force & Ignorance
V....D binkvideo Bink video
V....D bintext Binary text
V....D bmp BMP (Windows and OS/2 bitmap)
V....D bmv_video Discworld II BMV video
V....D brender_pix BRender PIX image
V....D c93 Interplay C93
V....D cavs Chinese AVS (Audio Video Standard) (AVS1-P2, JiZhun profile)
V....D cdgraphics CD Graphics video
V....D cdxl Commodore CDXL video
VF...D cfhd Cineform HD
V....D cinepak Cinepak
V....D cljr Cirrus Logic AccuPak
V....D cllc Canopus Lossless Codec
V....D eacmv Electronic Arts CMV video (codec cmv)
V....D cpia CPiA video format
V....D camstudio CamStudio (codec cscd)
V....D cyuv Creative YUV (CYUV)
V.S..D dds DirectDraw Surface image decoder
V....D dfa Chronomaster DFA
V.S..D dirac BBC Dirac VC-2
VFS..D dnxhd VC3/DNxHD
V....D dpx DPX (Digital Picture Exchange) image
V....D dsicinvideo Delphine Software International CIN video
V.S..D dvvideo DV (Digital Video)
V....D dxa Feeble Files/ScummVM DXA
V....D dxtory Dxtory
VFS..D dxv Resolume DXV
V....D escape124 Escape 124
V....D escape130 Escape 130
VFS..D exr OpenEXR image
VFS..D ffv1 FFmpeg video codec #1
VF..BD ffvhuff Huffyuv FFmpeg variant
V.S..D fic Mirillis FIC
V....D flashsv Flash Screen Video v1
V....D flashsv2 Flash Screen Video v2
V....D flic Autodesk Animator Flic video
V...BD flv FLV / Sorenson Spark / Sorenson H.263 (Flash Video) (codec flv1)
VF...D fraps Fraps
V....D frwu Forward Uncompressed
V....D g2m Go2Meeting
V....D gif GIF (Graphics Interchange Format)
V....D h261 H.261
V...BD h263 H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2
V...BD h263i Intel H.263
V...BD h263p H.263 / H.263-1996, H.263+ / H.263-1998 / H.263 version 2
VFS..D h264 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
VFS..D hap Vidvox Hap decoder
VFS..D hevc HEVC (High Efficiency Video Coding)
V....D hnm4video HNM 4 video
V....D hq_hqa Canopus HQ/HQA
V.S..D hqx Canopus HQX
VF..BD huffyuv Huffyuv / HuffYUV
V....D idcinvideo id Quake II CIN video (codec idcin)
V....D idf iCEDraw text
V....D iff IFF ACBM/ANIM/DEEP/ILBM/PBM/RGB8/RGBN (codec iff_ilbm)
V....D indeo2 Intel Indeo 2
V....D indeo3 Intel Indeo 3
V....D indeo4 Intel Indeo Video Interactive 4
V....D indeo5 Intel Indeo Video Interactive 5
V....D interplayvideo Interplay MVE video
VFS..D jpeg2000 JPEG 2000
V....D jpegls JPEG-LS
V....D jv Bitmap Brothers JV video
V....D kgv1 Kega Game Video
V....D kmvc Karl Morton's video codec
VF...D lagarith Lagarith lossless
V....D loco LOCO
V....D m101 Matrox Uncompressed SD
V....D eamad Electronic Arts Madcow Video (codec mad)
VFS..D magicyuv MagicYUV video
VF...D mdec Sony PlayStation MDEC (Motion DECoder)
VF...D mimic Mimic
V....D mjpeg MJPEG (Motion JPEG)
V....D mjpegb Apple MJPEG-B
V....D mmvideo American Laser Games MM Video
V....D motionpixels Motion Pixels video
V.S.BD mpeg1video MPEG-1 video
V.S.BD mpeg2video MPEG-2 video
V.S.BD mpegvideo MPEG-1 video (codec mpeg2video)
VF..BD mpeg4 MPEG-4 part 2
V....D msa1 MS ATC Screen
V...BD msmpeg4v1 MPEG-4 part 2 Microsoft variant version 1
V...BD msmpeg4v2 MPEG-4 part 2 Microsoft variant version 2
V...BD msmpeg4 MPEG-4 part 2 Microsoft variant version 3 (codec msmpeg4v3)
V....D msrle Microsoft RLE
V....D mss1 MS Screen 1
V....D mss2 MS Windows Media Video V9 Screen
V....D msvideo1 Microsoft Video 1
V....D mszh LCL (LossLess Codec Library) MSZH
V....D mts2 MS Expression Encoder Screen
V....D mvc1 Silicon Graphics Motion Video Compressor 1
V....D mvc2 Silicon Graphics Motion Video Compressor 2
V....D mxpeg Mobotix MxPEG video
V....D nuv NuppelVideo/RTJPEG
V....D paf_video Amazing Studio Packed Animation File Video
V....D pam PAM (Portable AnyMap) image
V....D pbm PBM (Portable BitMap) image
V....D pcx PC Paintbrush PCX image
V....D pgm PGM (Portable GrayMap) image
V....D pgmyuv PGMYUV (Portable GrayMap YUV) image
V....D pictor Pictor/PC Paint
VF...D png PNG (Portable Network Graphics) image
V....D ppm PPM (Portable PixelMap) image
V.S..D prores ProRes
V.S..D prores_lgpl Apple ProRes (iCodec Pro) (codec prores)
V....D ptx V.Flash PTX image
V....D qdraw Apple QuickDraw
V....D qpeg Q-team QPEG
V....D qtrle QuickTime Animation (RLE) video
V....D r10k AJA Kona 10-bit RGB Codec
V....D r210 Uncompressed RGB 10-bit
V..... rawvideo raw video
V....D rl2 RL2 video
V....D roqvideo id RoQ video (codec roq)
V....D rpza QuickTime video (RPZA)
V....D rscc innoHeim/Rsupport Screen Capture Codec
V....D rv10 RealVideo 1.0
V....D rv20 RealVideo 2.0
VF...D rv30 RealVideo 3.0
VF...D rv40 RealVideo 4.0
V....D sanm LucasArts SANM/Smush video
V....D screenpresso Screenpresso
V....D sgi SGI image
V....D sgirle Silicon Graphics RLE 8-bit video
VF...D sheervideo BitJazz SheerVideo
V....D smackvid Smacker video (codec smackvideo)
V....D smc QuickTime Graphics (SMC)
V..... smvjpeg SMV JPEG
V....D snow Snow
V....D sp5x Sunplus JPEG (SP5X)
V....D sunrast Sun Rasterfile image
V....D svq1 Sorenson Vector Quantizer 1 / Sorenson Video 1 / SVQ1
V...BD svq3 Sorenson Vector Quantizer 3 / Sorenson Video 3 / SVQ3
V....D targa Truevision Targa image
V....D targa_y216 Pinnacle TARGA CineWave YUV16
V....D tdsc TDSC
V....D eatgq Electronic Arts TGQ video (codec tgq)
V....D eatgv Electronic Arts TGV video (codec tgv)
VF..BD theora Theora
V....D thp Nintendo Gamecube THP video
V....D tiertexseqvideo Tiertex Limited SEQ video
VF...D tiff TIFF image
V....D tmv 8088flex TMV
V....D eatqi Electronic Arts TQI Video (codec tqi)
V....D truemotion1 Duck TrueMotion 1.0
V....D truemotion2 Duck TrueMotion 2.0
V....D truemotion2rt Duck TrueMotion 2.0 Real Time
V....D camtasia TechSmith Screen Capture Codec (codec tscc)
V....D tscc2 TechSmith Screen Codec 2
V....D txd Renderware TXD (TeXture Dictionary) image
V....D ultimotion IBM UltiMotion (codec ulti)
VF...D utvideo Ut Video
V....D v210 Uncompressed 4:2:2 10-bit
V....D v210x Uncompressed 4:2:2 10-bit
V....D v308 Uncompressed packed 4:4:4
V....D v408 Uncompressed packed QT 4:4:4:4
V....D v410 Uncompressed 4:4:4 10-bit
V....D vb Beam Software VB
VF...D vble VBLE Lossless Codec
V....D vc1 SMPTE VC-1
V....D vc1image Windows Media Video 9 Image v2
V....D vcr1 ATI VCR1
V....D xl Miro VideoXL (codec vixl)
V....D vmdvideo Sierra VMD video
V....D vmnc VMware Screen Codec / VMware Video
VF..BD vp3 On2 VP3
V....D vp5 On2 VP5
V....D vp6 On2 VP6
V.S..D vp6a On2 VP6 (Flash version, with alpha channel)
V....D vp6f On2 VP6 (Flash version)
V....D vp7 On2 VP7
VFS..D vp8 On2 VP8
VF...D vp9 Google VP9
VF...D webp WebP image
V...BD wmv1 Windows Media Video 7
V...BD wmv2 Windows Media Video 8
V....D wmv3 Windows Media Video 9
V....D wmv3image Windows Media Video 9 Image
V....D wnv1 Winnov WNV1
V....D vqavideo Westwood Studios VQA (Vector Quantized Animation) video (codec ws_vqa)
V....D xan_wc3 Wing Commander III / Xan
V....D xan_wc4 Wing Commander IV / Xxan
V....D xbin eXtended BINary text
V....D xbm XBM (X BitMap) image
V..... xface X-face image
V....D xwd XWD (X Window Dump) image
V....D y41p Uncompressed YUV 4:1:1 12-bit
V....D ylc YUY2 Lossless Codec
V..... yop Psygnosis YOP Video
V....D yuv4 Uncompressed packed 4:2:0
V....D zerocodec ZeroCodec Lossless Video
V....D zlib LCL (LossLess Codec Library) ZLIB
V....D zmbv Zip Motion Blocks Video
A....D 8svx_exp 8SVX exponential
A....D 8svx_fib 8SVX fibonacci
A....D aac AAC (Advanced Audio Coding)
A....D aac_fixed AAC (Advanced Audio Coding) (codec aac)
A....D libfdk_aac Fraunhofer FDK AAC (codec aac)
A....D aac_latm AAC LATM (Advanced Audio Coding LATM syntax)
A....D ac3 ATSC A/52A (AC-3)
A....D ac3_fixed ATSC A/52A (AC-3) (codec ac3)
A....D adpcm_4xm ADPCM 4X Movie
A....D adpcm_adx SEGA CRI ADX ADPCM
A....D adpcm_afc ADPCM Nintendo Gamecube AFC
A....D adpcm_aica ADPCM Yamaha AICA
A....D adpcm_ct ADPCM Creative Technology
A....D adpcm_dtk ADPCM Nintendo Gamecube DTK
A....D adpcm_ea ADPCM Electronic Arts
A....D adpcm_ea_maxis_xa ADPCM Electronic Arts Maxis CDROM XA
A....D adpcm_ea_r1 ADPCM Electronic Arts R1
A....D adpcm_ea_r2 ADPCM Electronic Arts R2
A....D adpcm_ea_r3 ADPCM Electronic Arts R3
A....D adpcm_ea_xas ADPCM Electronic Arts XAS
A....D g722 G.722 ADPCM (codec adpcm_g722)
A....D g726 G.726 ADPCM (codec adpcm_g726)
A....D g726le G.726 ADPCM little-endian (codec adpcm_g726le)
A....D adpcm_ima_amv ADPCM IMA AMV
A....D adpcm_ima_apc ADPCM IMA CRYO APC
A....D adpcm_ima_dat4 ADPCM IMA Eurocom DAT4
A....D adpcm_ima_dk3 ADPCM IMA Duck DK3
A....D adpcm_ima_dk4 ADPCM IMA Duck DK4
A....D adpcm_ima_ea_eacs ADPCM IMA Electronic Arts EACS
A....D adpcm_ima_ea_sead ADPCM IMA Electronic Arts SEAD
A....D adpcm_ima_iss ADPCM IMA Funcom ISS
A....D adpcm_ima_oki ADPCM IMA Dialogic OKI
A....D adpcm_ima_qt ADPCM IMA QuickTime
A....D adpcm_ima_rad ADPCM IMA Radical
A....D adpcm_ima_smjpeg ADPCM IMA Loki SDL MJPEG
A....D adpcm_ima_wav ADPCM IMA WAV
A....D adpcm_ima_ws ADPCM IMA Westwood
A....D adpcm_ms ADPCM Microsoft
A....D adpcm_mtaf ADPCM MTAF
A....D adpcm_psx ADPCM Playstation
A....D adpcm_sbpro_2 ADPCM Sound Blaster Pro 2-bit
A....D adpcm_sbpro_3 ADPCM Sound Blaster Pro 2.6-bit
A....D adpcm_sbpro_4 ADPCM Sound Blaster Pro 4-bit
A....D adpcm_swf ADPCM Shockwave Flash
A....D adpcm_thp ADPCM Nintendo THP
A....D adpcm_thp_le ADPCM Nintendo THP (little-endian)
A....D adpcm_vima LucasArts VIMA audio
A....D adpcm_xa ADPCM CDROM XA
A....D adpcm_yamaha ADPCM Yamaha
AF...D alac ALAC (Apple Lossless Audio Codec)
A....D amrnb AMR-NB (Adaptive Multi-Rate NarrowBand) (codec amr_nb)
A....D amrwb AMR-WB (Adaptive Multi-Rate WideBand) (codec amr_wb)
A....D ape Monkey's Audio
A....D atrac1 ATRAC1 (Adaptive TRansform Acoustic Coding)
A....D atrac3 ATRAC3 (Adaptive TRansform Acoustic Coding 3)
A....D atrac3plus ATRAC3+ (Adaptive TRansform Acoustic Coding 3+) (codec atrac3p)
A....D on2avc On2 Audio for Video Codec (codec avc)
A....D binkaudio_dct Bink Audio (DCT)
A....D binkaudio_rdft Bink Audio (RDFT)
A....D bmv_audio Discworld II BMV audio
A....D comfortnoise RFC 3389 comfort noise generator
A....D cook Cook / Cooker / Gecko (RealAudio G2)
A..... dsd_lsbf DSD (Direct Stream Digital), least significant bit first
A..... dsd_lsbf_planar DSD (Direct Stream Digital), least significant bit first, planar
A..... dsd_msbf DSD (Direct Stream Digital), most significant bit first
A..... dsd_msbf_planar DSD (Direct Stream Digital), most significant bit first, planar
A....D dsicinaudio Delphine Software International CIN audio
A....D dss_sp Digital Speech Standard - Standard Play mode (DSS SP)
A....D dst DST (Digital Stream Transfer)
A....D dca DCA (DTS Coherent Acoustics) (codec dts)
A....D dvaudio Ulead DV Audio
A....D eac3 ATSC A/52B (AC-3, E-AC-3)
A....D evrc EVRC (Enhanced Variable Rate Codec)
AF...D flac FLAC (Free Lossless Audio Codec)
A....D g723_1 G.723.1
A....D g729 G.729
A....D gsm GSM
A....D gsm_ms GSM Microsoft variant
A....D iac IAC (Indeo Audio Coder)
A....D imc IMC (Intel Music Coder)
A....D interplay_dpcm DPCM Interplay
A....D interplayacm Interplay ACM
A....D mace3 MACE (Macintosh Audio Compression/Expansion) 3:1
A....D mace6 MACE (Macintosh Audio Compression/Expansion) 6:1
A....D metasound Voxware MetaSound
A....D mlp MLP (Meridian Lossless Packing)
A....D mp1 MP1 (MPEG audio layer 1)
A....D mp1float MP1 (MPEG audio layer 1) (codec mp1)
A....D mp2 MP2 (MPEG audio layer 2)
A....D mp2float MP2 (MPEG audio layer 2) (codec mp2)
A....D mp3 MP3 (MPEG audio layer 3)
A....D mp3float MP3 (MPEG audio layer 3) (codec mp3)
A....D mp3adu ADU (Application Data Unit) MP3 (MPEG audio layer 3)
A....D mp3adufloat ADU (Application Data Unit) MP3 (MPEG audio layer 3) (codec mp3adu)
A....D mp3on4 MP3onMP4
A....D mp3on4float MP3onMP4 (codec mp3on4)
A....D als MPEG-4 Audio Lossless Coding (ALS) (codec mp4als)
A....D mpc7 Musepack SV7 (codec musepack7)
A....D mpc8 Musepack SV8 (codec musepack8)
A....D nellymoser Nellymoser Asao
A....D opus Opus
A....D paf_audio Amazing Studio Packed Animation File Audio
A....D pcm_alaw PCM A-law / G.711 A-law
A....D pcm_bluray PCM signed 16|20|24-bit big-endian for Blu-ray media
A....D pcm_dvd PCM signed 16|20|24-bit big-endian for DVD media
A....D pcm_f32be PCM 32-bit floating point big-endian
A....D pcm_f32le PCM 32-bit floating point little-endian
A....D pcm_f64be PCM 64-bit floating point big-endian
A....D pcm_f64le PCM 64-bit floating point little-endian
A....D pcm_lxf PCM signed 20-bit little-endian planar
A....D pcm_mulaw PCM mu-law / G.711 mu-law
A....D pcm_s16be PCM signed 16-bit big-endian
A....D pcm_s16be_planar PCM signed 16-bit big-endian planar
A....D pcm_s16le PCM signed 16-bit little-endian
A....D pcm_s16le_planar PCM signed 16-bit little-endian planar
A....D pcm_s24be PCM signed 24-bit big-endian
A....D pcm_s24daud PCM D-Cinema audio signed 24-bit
A....D pcm_s24le PCM signed 24-bit little-endian
A....D pcm_s24le_planar PCM signed 24-bit little-endian planar
A....D pcm_s32be PCM signed 32-bit big-endian
A....D pcm_s32le PCM signed 32-bit little-endian
A....D pcm_s32le_planar PCM signed 32-bit little-endian planar
A....D pcm_s64be PCM signed 64-bit big-endian
A....D pcm_s64le PCM signed 64-bit little-endian
A....D pcm_s8 PCM signed 8-bit
A....D pcm_s8_planar PCM signed 8-bit planar
A....D pcm_u16be PCM unsigned 16-bit big-endian
A....D pcm_u16le PCM unsigned 16-bit little-endian
A....D pcm_u24be PCM unsigned 24-bit big-endian
A....D pcm_u24le PCM unsigned 24-bit little-endian
A....D pcm_u32be PCM unsigned 32-bit big-endian
A....D pcm_u32le PCM unsigned 32-bit little-endian
A....D pcm_u8 PCM unsigned 8-bit
A....D pcm_zork PCM Zork
A....D qcelp QCELP / PureVoice
A....D qdm2 QDesign Music Codec 2
A....D real_144 RealAudio 1.0 (14.4K) (codec ra_144)
A....D real_288 RealAudio 2.0 (28.8K) (codec ra_288)
A....D ralf RealAudio Lossless
A....D roq_dpcm DPCM id RoQ
A....D s302m SMPTE 302M
A....D sdx2_dpcm DPCM Squareroot-Delta-Exact
A....D shorten Shorten
A....D sipr RealAudio SIPR / ACELP.NET
A....D smackaud Smacker audio (codec smackaudio)
A....D sol_dpcm DPCM Sol
A..X.D sonic Sonic
AF...D tak TAK (Tom's lossless Audio Kompressor)
A....D truehd TrueHD
A....D truespeech DSP Group TrueSpeech
AF...D tta TTA (True Audio)
A....D twinvq VQF TwinVQ
A....D vmdaudio Sierra VMD audio
A....D vorbis Vorbis
A....D wavesynth Wave synthesis pseudo-codec
AF...D wavpack WavPack
A....D ws_snd1 Westwood Audio (SND1) (codec westwood_snd1)
A....D wmalossless Windows Media Audio Lossless
A....D wmapro Windows Media Audio 9 Professional
A....D wmav1 Windows Media Audio 1
A....D wmav2 Windows Media Audio 2
A....D wmavoice Windows Media Audio Voice
A....D xan_dpcm DPCM Xan
A....D xma1 Xbox Media Audio 1
A....D xma2 Xbox Media Audio 2
S..... ssa ASS (Advanced SubStation Alpha) subtitle (codec ass)
S..... ass ASS (Advanced SubStation Alpha) subtitle
S..... dvbsub DVB subtitles (codec dvb_subtitle)
S..... dvdsub DVD subtitles (codec dvd_subtitle)
S..... cc_dec Closed Caption (EIA-608 / CEA-708) Decoder (codec eia_608)
S..... pgssub HDMV Presentation Graphic Stream subtitles (codec hdmv_pgs_subtitle)
S..... jacosub JACOsub subtitle
S..... microdvd MicroDVD subtitle
S..... mov_text 3GPP Timed Text subtitle
S..... mpl2 MPL2 subtitle
S..... pjs PJS subtitle
S..... realtext RealText subtitle
S..... sami SAMI subtitle
S..... stl Spruce subtitle format
S..... srt SubRip subtitle (codec subrip)
S..... subrip SubRip subtitle
S..... subviewer SubViewer subtitle
S..... subviewer1 SubViewer1 subtitle
S..... text Raw text subtitle
S..... vplayer VPlayer subtitle
S..... webvtt WebVTT subtitle
S..... xsub XSUBAny idea what I did wrong when building FFMPEG ?
Here’s a link to the video file that caused the problem : step-2.mov
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Open Media Developers Track at OVC 2011
11 octobre 2011, par silviaThe Open Video Conference that took place on 10-12 September was so overwhelming, I’ve still not been able to catch my breath ! It was a dense three days for me, even though I only focused on the technology sessions of the conference and utterly missed out on all the policy and content discussions.
Roughly 60 people participated in the Open Media Software (OMS) developers track. This was an amazing group of people capable and willing to shape the future of video technology on the Web :
- HTML5 video developers from Apple, Google, Opera, and Mozilla (though we missed the NZ folks),
- codec developers from WebM, Xiph, and MPEG,
- Web video developers from YouTube, JWPlayer, Kaltura, VideoJS, PopcornJS, etc.,
- content publishers from Wikipedia, Internet Archive, YouTube, Netflix, etc.,
- open source tool developers from FFmpeg, gstreamer, flumotion, VideoLAN, PiTiVi, etc,
- and many more.
To provide a summary of all the discussions would be impossible, so I just want to share the key take-aways that I had from the main sessions.
WebRTC : Realtime Communications and HTML5
Tim Terriberry (Mozilla), Serge Lachapelle (Google) and Ethan Hugg (CISCO) moderated this session together (slides). There are activities both at the W3C and at IETF – the ones at IETF are supposed to focus on protocols, while the W3C ones on HTML5 extensions.
The current proposal of a PeerConnection API has been implemented in WebKit/Chrome as open source. It is expected that Firefox will have an add-on by Q1 next year. It enables video conferencing, including media capture, media encoding, signal processing (echo cancellation etc), secure transmission, and a data stream exchange.
Current discussions are around the signalling protocol and whether SIP needs to be required by the standard. Further, the codec question is under discussion with a question whether to mandate VP8 and Opus, since transcoding gateways are not desirable. Another question is how to measure the quality of the connection and how to report errors so as to allow adaptation.
What always amazes me around RTC is the sheer number of specialised protocols that seem to be required to implement this. WebRTC does not disappoint : in fact, the question was asked whether there could be a lighter alternative than to re-use dozens of years of protocol development – is it over-engineered ? Can desktop players connect to a WebRTC session ?
We are already in a second or third revision of this part of the HTML5 specification and yet it seems the requirements are still being collected. I’m quietly confident that everything is done to make the lives of the Web developer easier, but it sure looks like a huge task.
The Missing Link : Flash to HTML5
Zohar Babin (Kaltura) and myself moderated this session and I must admit that this session was the biggest eye-opener for me amongst all the sessions. There was a large number of Flash developers present in the room and that was great, because sometimes we just don’t listen enough to lessons learnt in the past.
This session gave me one of those aha-moments : it the form of the Flash appendBytes() API function.
The appendBytes() function allows a Flash developer to take a byteArray out of a connected video resource and do something with it – such as feed it to a video for display. When I heard that Web developers want that functionality for JavaScript and the video element, too, I instinctively rejected the idea wondering why on earth would a Web developer want to touch encoded video bytes – why not leave that to the browser.
But as it turns out, this is actually a really powerful enabler of functionality. For example, you can use it to :
- display mid-roll video ads as part of the same video element,
- sequence playlists of videos into the same video element,
- implement DVR functionality (high-speed seeking),
- do mash-ups,
- do video editing,
- adaptive streaming.
This totally blew my mind and I am now completely supportive of having such a function in HTML5. Together with media fragment URIs you could even leave all the header download management for resources to the Web browser and just request time ranges from a video through an appendBytes() function. This would be easier on the Web developer than having to deal with byte ranges and making sure that appropriate decoding pipelines are set up.
Standards for Video Accessibility
Philip Jagenstedt (Opera) and myself moderated this session. We focused on the HTML5 track element and the WebVTT file format. Many issues were identified that will still require work.
One particular topic was to find a standard means of rendering the UI for caption, subtitle, und description selection. For example, what icons should be used to indicate that subtitles or captions are available. While this is not part of the HTML5 specification, it’s still important to get this right across browsers since otherwise users will get confused with diverging interfaces.
Chaptering was discussed and a particular need to allow URLs to directly point at chapters was expressed. I suggested the use of named Media Fragment URLs.
The use of WebVTT for descriptions for the blind was also discussed. A suggestion was made to use the voice tag <v> to allow for “styling” (i.e. selection) of the screen reader voice.
Finally, multitrack audio or video resources were also discussed and the @mediagroup attribute was explained. A question about how to identify the language used in different alternative dubs was asked. This is an issue because @srclang is not on audio or video, only on text, so it’s a missing feature for the multitrack API.
Beyond this session, there was also a breakout session on WebVTT and the track element. As a consequence, a number of bugs were registered in the W3C bug tracker.
WebM : Testing, Metrics and New features
This session was moderated by John Luther and John Koleszar, both of the WebM Project. They started off with a presentation on current work on WebM, which includes quality testing and improvements, and encoder speed improvement. Then they moved on to questions about how to involve the community more.
The community criticised that communication of what is happening around WebM is very scarce. More sharing of information was requested, including a move to using open Google+ hangouts instead of Google internal video conferences. More use of the public bug tracker can also help include the community better.
Another pain point of the community was that code is introduced and removed without much feedback. It was requested to introduce a peer review process. Also it was requested that example code snippets are published when new features are announced so others can replicate the claims.
This all indicates to me that the WebM project is increasingly more open, but that there is still a lot to learn.
Standards for HTTP Adaptive Streaming
This session was moderated by Frank Galligan and Aaron Colwell (Google), and Mark Watson (Netflix).
Mark started off by giving us an introduction to MPEG DASH, the MPEG file format for HTTP adaptive streaming. MPEG has just finalized the format and he was able to show us some examples. DASH is XML-based and thus rather verbose. It is covering all eventualities of what parameters could be switched during transmissions, which makes it very broad. These include trick modes e.g. for fast forwarding, 3D, multi-view and multitrack content.
MPEG have defined profiles – one for live streaming which requires chunking of the files on the server, and one for on-demand which requires keyframe alignment of the files. There are clear specifications for how to do these with MPEG. Such profiles would need to be created for WebM and Ogg Theora, too, to make DASH universally applicable.
Further, the Web case needs a more restrictive adaptation approach, since the video element’s API is already accounting for some of the features that DASH provides for desktop applications. So, a Web-specific profile of DASH would be required.
Then Aaron introduced us to the MediaSource API and in particular the webkitSourceAppend() extension that he has been experimenting with. It is essentially an implementation of the appendBytes() function of Flash, which the Web developers had been asking for just a few sessions earlier. This was likely the biggest announcement of OVC, alas a quiet and technically-focused one.
Aaron explained that he had been trying to find a way to implement HTTP adaptive streaming into WebKit in a way in which it could be standardised. While doing so, he also came across other requirements around such chunked video handling, in particular around dynamic ad insertion, live streaming, DVR functionality (fast forward), constraint video editing, and mashups. While trying to sort out all these requirements, it became clear that it would be very difficult to implement strategies for stream switching, buffering and delivery of video chunks into the browser when so many different and likely contradictory requirements exist. Also, once an approach is implemented and specified for the browser, it becomes very difficult to innovate on it.
Instead, the easiest way to solve it right now and learn about what would be necessary to implement into the browser would be to actually allow Web developers to queue up a chunk of encoded video into a video element for decoding and display. Thus, the webkitSourceAppend() function was born (specification).
The proposed extension to the HTMLMediaElement is as follows :
partial interface HTMLMediaElement // URL passed to src attribute to enable the media source logic. readonly attribute [URL] DOMString webkitMediaSourceURL ;
bool webkitSourceAppend(in Uint8Array data) ;
// end of stream status codes.
const unsigned short EOS_NO_ERROR = 0 ;
const unsigned short EOS_NETWORK_ERR = 1 ;
const unsigned short EOS_DECODE_ERR = 2 ;void webkitSourceEndOfStream(in unsigned short status) ;
// states
const unsigned short SOURCE_CLOSED = 0 ;
const unsigned short SOURCE_OPEN = 1 ;
const unsigned short SOURCE_ENDED = 2 ;readonly attribute unsigned short webkitSourceState ;
;The code is already checked into WebKit, but commented out behind a command-line compiler flag.
Frank then stepped forward to show how webkitSourceAppend() can be used to implement HTTP adaptive streaming. His example uses WebM – there are no examples with MPEG or Ogg yet.
The chunks that Frank’s demo used were 150 video frames long (6.25s) and 5s long audio. Stream switching only switched video, since audio data is much lower bandwidth and more important to retain at high quality. Switching was done on multiplexed files.
Every chunk requires an XHR range request – this could be optimised if the connections were kept open per adaptation. Seeking works, too, but since decoding requires download of a whole chunk, seeking latency is determined by the time it takes to download and decode that chunk.
Similar to DASH, when using this approach for live streaming, the server has to produce one file per chunk, since byte range requests are not possible on a continuously growing file.
Frank did not use DASH as the manifest format for his HTTP adaptive streaming demo, but instead used a hacked-up custom XML format. It would be possible to use JSON or any other format, too.
After this session, I was actually completely blown away by the possibilities that such a simple API extension allows. If I wasn’t sold on the idea of a appendBytes() function in the earlier session, this one completely changed my mind. While I still believe we need to standardise a HTTP adaptive streaming file format that all browsers will support for all codecs, and I still believe that a native implementation for support of such a file format is necessary, I also believe that this approach of webkitSourceAppend() is what HTML needs – and maybe it needs it faster than native HTTP adaptive streaming support.
Standards for Browser Video Playback Metrics
This session was moderated by Zachary Ozer and Pablo Schklowsky (JWPlayer). Their motivation for the topic was, in fact, also HTTP adaptive streaming. Once you leave the decisions about when to do stream switching to JavaScript (through a function such a wekitSourceAppend()), you have to expose stream metrics to the JS developer so they can make informed decisions. The other use cases is, of course, monitoring of the quality of video delivery for reporting to the provider, who may then decide to change their delivery environment.
The discussion found that we really care about metrics on three different levels :
- measuring the network performance (bandwidth)
- measuring the decoding pipeline performance
- measuring the display quality
In the end, it seemed that work previously done by Steve Lacey on a proposal for video metrics was generally acceptable, except for the playbackJitter metric, which may be too aggregate to mean much.
Device Inputs / A/V in the Browser
I didn’t actually attend this session held by Anant Narayanan (Mozilla), but from what I heard, the discussion focused on how to manage permission of access to video camera, microphone and screen, e.g. when multiple applications (tabs) want access or when the same site wants access in a different session. This may apply to real-time communication with screen sharing, but also to photo sharing, video upload, or canvas access to devices e.g. for time lapse photography.
Open Video Editors
This was another session that I wasn’t able to attend, but I believe the creation of good open source video editing software and similar video creation software is really crucial to giving video a broader user appeal.
Jeff Fortin (PiTiVi) moderated this session and I was fascinated to later see his analysis of the lifecycle of open source video editors. It is shocking to see how many people/projects have tried to create an open source video editor and how many have stopped their project. It is likely that the creation of a video editor is such a complex challenge that it requires a larger and more committed open source project – single people will just run out of steam too quickly. This may be comparable to the creation of a Web browser (see the size of the Mozilla project) or a text processing system (see the size of the OpenOffice project).
Jeff also mentioned the need to create open video editor standards around playlist file formats etc. Possibly the Open Video Alliance could help. In any case, something has to be done in this space – maybe this would be a good topic to focus next year’s OVC on ?
Monday’s Breakout Groups
The conference ended officially on Sunday night, but we had a third day of discussions / hackday at the wonderful New York Lawschool venue. We had collected issues of interest during the two previous days and organised the breakout groups on the morning (Schedule).
In the Content Protection/DRM session, Mark Watson from Netflix explained how their API works and that they believe that all we need in browsers is a secure way to exchange keys and an indicator of protection scheme is used – the actual protection scheme would not be implemented by the browser, but be provided by the underlying system (media framework/operating system). I think that until somebody actually implements something in a browser fork and shows how this can be done, we won’t have much progress. In my understanding, we may also need to disable part of the video API for encrypted content, because otherwise you can always e.g. grab frames from the video element into canvas and save them from there.
In the Playlists and Gapless Playback session, there was massive brainstorming about what new cool things can be done with the video element in browsers if playback between snippets can be made seamless. Further discussions were about a standard playlist file formats (such as XSPF, MRSS or M3U), media fragment URIs in playlists for mashups, and the need to expose track metadata for HTML5 media elements.
What more can I say ? It was an amazing three days and the complexity of problems that we’re dealing with is a tribute to how far HTML5 and open video has already come and exciting news for the kind of applications that will be possible (both professional and community) once we’ve solved the problems of today. It will be exciting to see what progress we will have made by next year’s conference.
Thanks go to Google for sponsoring my trip to OVC.
UPDATE : We actually have a mailing list for open media developers who are interested in these and similar topics – do join at http://lists.annodex.net/cgi-bin/mailman/listinfo/foms.
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