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• Download a video from blob:https url from eventive

  26 août 2020, par jjcasmar

  I want to download a video from eventive but the tag contains a blob url (blob :https://watch.eventive.org/**************).

  


  I have been reading some answers to similar questions but they all assume that the video has a mp3u8 file extension, which in my case doesn't.

  


  I have also tried to directly download that url (removing the blob :) with curl, but I obtained a html code which I cant really understand, which contains a lot of references to javascript files.

  


  Any tip would be really helpful.

  


  Edit :

  


  I have been doing some more tests and I have been able to found a url to a manifest file which points apparently to the video data. I have tried to open that url using VLC and it loads some info about the video, and it even plays it, but the screen is completely black.

  


  I have also tried to download it using ffmpeg but it gives a bunch of errors.

  


  ffmpeg -i https://eventiveprod-usea.streaming.media.azure.net/02968382-069a-4f02-ab3b-67c0b5a8d5b7/5f427f2d65a569006ebd326c.ism/manifest\(format\=mpd-time-csf\)  output.mp4


  


  ffmpeg output

  


  ffmpeg version n4.3.1 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 10.1.0 (GCC)
  configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-avisynth --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libmfx --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librav1e --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-nvdec --enable-nvenc --enable-omx --enable-shared --enable-version3
  libavutil      56. 51.100 / 56. 51.100
  libavcodec     58. 91.100 / 58. 91.100
  libavformat    58. 45.100 / 58. 45.100
  libavdevice    58. 10.100 / 58. 10.100
  libavfilter     7. 85.100 /  7. 85.100
  libswscale      5.  7.100 /  5.  7.100
  libswresample   3.  7.100 /  3.  7.100
  libpostproc    55.  7.100 / 55.  7.100
[h264 @ 0x556c1e280bc0] top block unavailable for requested intra mode
[h264 @ 0x556c1e280bc0] error while decoding MB 34 0, bytestream 41478                                                                                                                                                                                                        
[h264 @ 0x556c1e280bc0] concealing 8160 DC, 8160 AC, 8160 MV errors in I frame
[h264 @ 0x556c1e2ce440] top block unavailable for requested intra mode -1
[h264 @ 0x556c1e2ce440] error while decoding MB 34 0, bytestream 22093                                                                                                                                                                                                        
[h264 @ 0x556c1e2ce440] concealing 3600 DC, 3600 AC, 3600 MV errors in I frame
[h264 @ 0x556c1e2f9f40] top block unavailable for requested intra mode -1
[h264 @ 0x556c1e2f9f40] error while decoding MB 24 0, bytestream 15117                                                                                                                                                                                                        
[h264 @ 0x556c1e2f9f40] concealing 2040 DC, 2040 AC, 2040 MV errors in I frame
[h264 @ 0x556c1e333bc0] top block unavailable for requested intra mode -1
[h264 @ 0x556c1e333bc0] error while decoding MB 17 0, bytestream 8716                                                                                                                                                                                                         
[h264 @ 0x556c1e333bc0] concealing 920 DC, 920 AC, 920 MV errors in I frame
[aac @ 0x556c1e3745c0] channel element 2.8 is not allocated
Input #0, dash, from 'https://eventiveprod-usea.streaming.media.azure.net/02968382-069a-4f02-ab3b-67c0b5a8d5b7/5f427f2d65a569006ebd326c.ism/manifest(format=mpd-time-csf)':
  Duration: 00:21:18.00, start: 0.066000, bitrate: 0 kb/s
  Program 0 
    Stream #0:0: Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 1317 kb/s, 29.97 fps, 29.97 tbr, 10000k tbn, 59.94 tbc
    Metadata:
      variant_bitrate : 1770930
      id              : 1_V_video_1
    Stream #0:1: Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 686 kb/s, 29.97 fps, 29.97 tbr, 10000k tbn, 59.94 tbc
    Metadata:
      variant_bitrate : 904295
      id              : 1_V_video_2
    Stream #0:2: Video: h264 (High) (avc1 / 0x31637661), yuv420p, 960x540 [SAR 1:1 DAR 16:9], 495 kb/s, 29.97 fps, 29.97 tbr, 10000k tbn, 59.94 tbc
    Metadata:
      variant_bitrate : 572685
      id              : 1_V_video_3
    Stream #0:3: Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x360 [SAR 1:1 DAR 16:9], 308 kb/s, 29.97 fps, 29.97 tbr, 10000k tbn, 59.94 tbc
    Metadata:
      variant_bitrate : 301036
      id              : 1_V_video_4
    Stream #0:4(en): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s
    Metadata:
      variant_bitrate : 127999
      id              : 5_A_aac_eng_2_127999
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:4 -> #0:1 (aac (native) -> aac (native))
Press [q] to stop, [?] for help
[aac @ 0x556c1e392dc0] channel element 2.8 is not allocated
Error while decoding stream #0:4: Invalid data found when processing input                                                                                                                                                                                                    
[h264 @ 0x556c1e3da900] top block unavailable for requested intra mode                                                                                                                                                                                                        
[h264 @ 0x556c1e3da900] error while decoding MB 34 0, bytestream 41478                                                                                                                                                                                                        
[aac @ 0x556c1e392dc0] Reserved bit set.                                                                                                                                                                                                                                      
[aac @ 0x556c1e392dc0] Number of bands (13) exceeds limit (11).                                                                                                                                                                                                               
[h264 @ 0x556c1e3da900] concealing 8160 DC, 8160 AC, 8160 MV errors in I frame
Error while decoding stream #0:4: Invalid data found when processing input
[aac @ 0x556c1e392dc0] channel element 2.4 is not allocated                                                                                                                                                                                                                   
Error while decoding stream #0:4: Invalid data found when processing input                                                                                                                                                                                                    
[aac @ 0x556c1e392dc0] Multiple frames in a packet.
...
[libx264 @ 0x5588338c2d00] frame I:1     Avg QP: 4.13  size:   421
[libx264 @ 0x5588338c2d00] frame P:32    Avg QP:14.06  size:  1216
[libx264 @ 0x5588338c2d00] frame B:96    Avg QP:20.52  size:   306
[libx264 @ 0x5588338c2d00] consecutive B-frames:  0.8%  0.0%  0.0% 99.2%
[libx264 @ 0x5588338c2d00] mb I  I16..4: 100.0%  0.0%  0.0%
[libx264 @ 0x5588338c2d00] mb P  I16..4:  0.6%  0.6%  0.0%  P16..4:  9.4%  0.3%  0.3%  0.0%  0.0%    skip:88.9%
[libx264 @ 0x5588338c2d00] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8:  3.7%  0.0%  0.0%  direct: 0.0%  skip:96.2%  L0:53.5% L1:46.3% BI: 0.2%
[libx264 @ 0x5588338c2d00] 8x8 transform intra:13.0% inter:86.8%
[libx264 @ 0x5588338c2d00] coded y,uvDC,uvAC intra: 1.3% 0.8% 0.2% inter: 0.2% 0.2% 0.0%
[libx264 @ 0x5588338c2d00] i16 v,h,dc,p: 98%  0%  2%  0%
[libx264 @ 0x5588338c2d00] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 33%  2% 64%  0%  0%  0%  0%  0%  0%
[libx264 @ 0x5588338c2d00] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 29% 18% 42%  3%  1%  1%  2%  2%  1%
[libx264 @ 0x5588338c2d00] i8c dc,h,v,p: 99%  0%  0%  0%
[libx264 @ 0x5588338c2d00] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0x5588338c2d00] ref P L0: 86.7%  1.2%  8.8%  3.3%
[libx264 @ 0x5588338c2d00] ref B L0: 62.7% 35.4%  1.9%
[libx264 @ 0x5588338c2d00] ref B L1: 96.1%  3.9%
[libx264 @ 0x5588338c2d00] kb/s:127.70
Conversion failed!


  


• ffmpeg "Manifest too large" when downloading youtube video

  22 avril 2024, par ynn

  TL ;DR

  


  I'm trying to programmatically download a part of a YouTube video. The widely known procedure doesn't work for some videos and I'd like to overcome this situation.

  


  ---

  


  Context

  


  I'm trying to programmatically download a part of a YouTube video. As described in How to download portion of video with youtube-dl command ?, you can achieve this by the following commands.

  


  #Converts a human-readable URL to longer URLs for internal use.
~ $ youtube-dl --get-url 'https://www.youtube.com/watch?v=POrfo478HRI'
https://r1---sn-3pm76n76.googlevideo.com/videoplayback?expire=1597593009&ei=UQE5X7bXEYqO4QLs17KACQ&ip=10.100.238.99&id=o-AD0HfadoeimIbuf9t8Anru5X9V7cER08YyOz4iKZOCHL&itag=299&aitags=133%2C134%2C135%2C136%2C137%2C160%2C242%2C243%2C244%2C247%2C248%2C278%2C298%2C299%2C302%2C303&source=youtube&requiressl=yes&mh=NV&mm=31%2C26&mn=sn-3pm76n76%2Csn-oguesnze&ms=au%2Conr&mv=m&mvi=1&pl=17&initcwndbps=908750&vprv=1&mime=video%2Fmp4&gir=yes&clen=9205054989&dur=17931.000&lmt=1597347724488304&mt=1597571322&fvip=1&keepalive=yes&fexp=23883098&c=WEB&txp=7316222&sparams=expire%2Cei%2Cip%2Cid%2Caitags%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIgYDqTm0CnLfG0kxsYNrAdtAUYB7alnowiaBArU8R5bBwCIQDeCRDJHFO_PWcnbeFaJvip80deuboN4Pi1x3eRhJBxlQ%3D%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRgIhAKTkyTIGVkbWWVx4lqFz77rOdG1FzkM5XuTnYOqtHT4oAiEA9u1R47jPz-mjj4DRXpqqqpUbfaFMW36KbG_pR2jovFM%3D&ratebypass=yes
https://r1---sn-3pm76n76.googlevideo.com/videoplayback?expire=1597593009&ei=UQE5X7bXEYqO4QLs17KACQ&ip=10.100.238.99&id=o-AD0HfadoeimIbuf9t8Anru5X9V7cER08YyOz4iKZOCHL&itag=251&source=youtube&requiressl=yes&mh=NV&mm=31%2C26&mn=sn-3pm76n76%2Csn-oguesnze&ms=au%2Conr&mv=m&mvi=1&pl=17&initcwndbps=908750&vprv=1&mime=audio%2Fwebm&gir=yes&clen=268945126&dur=17931.001&lmt=1597348111385641&mt=1597571322&fvip=1&keepalive=yes&fexp=23883098&c=WEB&txp=7311222&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRgIhAK8XGu3vHucHwqERZ7TQniuvKEd-NTbMkwZbu8EXJ5E3AiEAiS7OYFOcsIrD2xp-AJNzucj1H9ZKMlmkCl_sU7__dZo%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRgIhAKTkyTIGVkbWWVx4lqFz77rOdG1FzkM5XuTnYOqtHT4oAiEA9u1R47jPz-mjj4DRXpqqqpUbfaFMW36KbG_pR2jovFM%3D&ratebypass=yes

#Stores the result to a variable.
~ $ url_video_part='https://r1---sn-3pm76n76.googlevideo.com/videoplayback?expire=1597593009&ei=UQE5X7bXEYqO4QLs17KACQ&ip=10.100.238.99&id=o-AD0HfadoeimIbuf9t8Anru5X9V7cER08YyOz4iKZOCHL&itag=299&aitags=133%2C134%2C135%2C136%2C137%2C160%2C242%2C243%2C244%2C247%2C248%2C278%2C298%2C299%2C302%2C303&source=youtube&requiressl=yes&mh=NV&mm=31%2C26&mn=sn-3pm76n76%2Csn-oguesnze&ms=au%2Conr&mv=m&mvi=1&pl=17&initcwndbps=908750&vprv=1&mime=video%2Fmp4&gir=yes&clen=9205054989&dur=17931.000&lmt=1597347724488304&mt=1597571322&fvip=1&keepalive=yes&fexp=23883098&c=WEB&txp=7316222&sparams=expire%2Cei%2Cip%2Cid%2Caitags%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRQIgYDqTm0CnLfG0kxsYNrAdtAUYB7alnowiaBArU8R5bBwCIQDeCRDJHFO_PWcnbeFaJvip80deuboN4Pi1x3eRhJBxlQ%3D%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRgIhAKTkyTIGVkbWWVx4lqFz77rOdG1FzkM5XuTnYOqtHT4oAiEA9u1R47jPz-mjj4DRXpqqqpUbfaFMW36KbG_pR2jovFM%3D&ratebypass=yes'

#Stores the result to a variable.
~ $ url_audio_part='https://r1---sn-3pm76n76.googlevideo.com/videoplayback?expire=1597593009&ei=UQE5X7bXEYqO4QLs17KACQ&ip=10.100.238.99&id=o-AD0HfadoeimIbuf9t8Anru5X9V7cER08YyOz4iKZOCHL&itag=251&source=youtube&requiressl=yes&mh=NV&mm=31%2C26&mn=sn-3pm76n76%2Csn-oguesnze&ms=au%2Conr&mv=m&mvi=1&pl=17&initcwndbps=908750&vprv=1&mime=audio%2Fwebm&gir=yes&clen=268945126&dur=17931.001&lmt=1597348111385641&mt=1597571322&fvip=1&keepalive=yes&fexp=23883098&c=WEB&txp=7311222&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cvprv%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=AOq0QJ8wRgIhAK8XGu3vHucHwqERZ7TQniuvKEd-NTbMkwZbu8EXJ5E3AiEAiS7OYFOcsIrD2xp-AJNzucj1H9ZKMlmkCl_sU7__dZo%3D&lsparams=mh%2Cmm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AG3C_xAwRgIhAKTkyTIGVkbWWVx4lqFz77rOdG1FzkM5XuTnYOqtHT4oAiEA9u1R47jPz-mjj4DRXpqqqpUbfaFMW36KbG_pR2jovFM%3D&ratebypass=yes'

#Downloads the video for one minute from 12:45.
~ $ ffmpeg    -ss 12:45 -i "${url_video_part}"    -ss 12:45 -i "${url_audio_part}"    -t 1:00 output.mkv
frame= 3600 fps= 49 q=-1.0 Lsize=   27047kB time=00:00:59.99 bitrate=3692.9kbits/s speed=0.813x


  


  This does work perfectly.

  


  ---

  


  Problem

  


  For some videos^†1, the internal URLs are of the form https://manifest.googlevideo.com/... instead of https://RANDOM-STRING.googlevideo.com/... as in the example above.

  


  ~ $ youtube-dl --get-url 'https://www.youtube.com/watch?v=KRMfnvLODZQ'
https://manifest.googlevideo.com/api/manifest/dash/expire/1597593866/ei/qgQ5X5maN8-ilQSu15W4CQ/ip/10.100.238.99/id/KRMfnvLODZQ.1/source/yt_live_broadcast/requiressl/yes/hfr/all/as/fmp4_audio_clear%2Cwebm_audio_clear%2Cwebm2_audio_clear%2Cfmp4_sd_hd_clear%2Cwebm2_sd_hd_clear/force_finished/1/vprv/1/keepalive/yes/fexp/23883098/itag/0/playlist_type/DVR/sparams/expire%2Cei%2Cip%2Cid%2Csource%2Crequiressl%2Chfr%2Cas%2Cforce_finished%2Cvprv%2Citag%2Cplaylist_type/sig/AOq0QJ8wRQIhANYKQvKTN8BRmhp7--4tQp9aqRp_qIGjh472BTYLyJ62AiAautFF86xGDHOe7mYlYaZ1W86EM4k2e6UiJS9Q91dMog%3D%3D
https://manifest.googlevideo.com/api/manifest/dash/expire/1597593866/ei/qgQ5X5maN8-ilQSu15W4CQ/ip/10.100.238.99/id/KRMfnvLODZQ.1/source/yt_live_broadcast/requiressl/yes/hfr/all/as/fmp4_audio_clear%2Cwebm_audio_clear%2Cwebm2_audio_clear%2Cfmp4_sd_hd_clear%2Cwebm2_sd_hd_clear/force_finished/1/vprv/1/keepalive/yes/fexp/23883098/itag/0/playlist_type/DVR/sparams/expire%2Cei%2Cip%2Cid%2Csource%2Crequiressl%2Chfr%2Cas%2Cforce_finished%2Cvprv%2Citag%2Cplaylist_type/sig/AOq0QJ8wRQIhANYKQvKTN8BRmhp7--4tQp9aqRp_qIGjh472BTYLyJ62AiAautFF86xGDHOe7mYlYaZ1W86EM4k2e6UiJS9Q91dMog%3D%3D


  


  And downloading such videos always fails.

  


  ~ $ ffmpeg    -ss 12:45 -i "${url_video_part}"    -ss 12:45 -i "${url_audio_part}"    -t 1:00 output.mkv
[dash @ 0x55fa6a1a4400] Manifest too large: 3776722
https://manifest.googlevideo.com/...: Invalid data found when processing input


  


  Please note downloading full of such videos using youtube-dl alone succeeds.

  


  _{†1 : As far as we tested, recently (e.g. yesterday) uploaded videos have such URLs and when we retry the same youtube-dl --get-url command after a day or so, we get "innocent" URLs like in the first example.}

  


  ---

  


  Questions

  


  How can I download parts of such videos

  


  


  • by specifying additional options for ffmpeg,

    


  


  • by somehow forcefully retrieving internal URLs of the form https://RANDOM-STRING.googlevideo.com/...,

    


  


  • or by something which I have no idea at all ?

    


  


  


  My current workaround is just to wait for a day or two until the internal URLs change, which is much slower than downloading the full video and then cropping it.

  


  ---

  


  Environments

  


  ~ $ lsb_release -d
Description:    Arch Linux

~ $ ffmpeg -version
ffmpeg version n4.3.1 Copyright (c) 2000-2020 the FFmpeg developers
built with gcc 10.1.0 (GCC)
configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-avisynth --enable-fontconfig --enable-gmp --enable-gnutls --enable-gpl --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libdav1d --enable-libdrm --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libiec61883 --enable-libjack --enable-libmfx --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librav1e --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libssh --enable-libtheora --enable-libv4l2 --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxcb --enable-libxml2 --enable-libxvid --enable-nvdec --enable-nvenc --enable-omx --enable-shared --enable-version3
libavutil      56. 51.100 / 56. 51.100
libavcodec     58. 91.100 / 58. 91.100
libavformat    58. 45.100 / 58. 45.100
libavdevice    58. 10.100 / 58. 10.100
libavfilter     7. 85.100 /  7. 85.100
libswscale      5.  7.100 /  5.  7.100
libswresample   3.  7.100 /  3.  7.100
libpostproc    55.  7.100 / 55.  7.100

~ $ youtube-dl --version
2020.07.28


  


• ffmpeg status & quality / cuda (CPU/GPU)

  18 avril 2015, par cocco

  ffmpeg am i doing it right ?

  So much time has passed since i use ffmpeg to convert clips on my home web server, now that mp4 (h264 & aac) is the current overall standard (works on every console, smartphone, smartTV, pc) i decided to convert my old clips from various digital cameras to to this new container/codecs.

  1. less space & the same quality.
  2. compatibility
  3. support for tags (subler for mac)

  after some research i opted for ffmpeg because of various reasons

  1. commandline (i made my simple web interface with default settings wich i execute with php’s exec)
  2. the quality/size amount

  I read that many expensive video conversion softwares are not able to handle low bitrate videos properly. I also tested some of them and personally i could not find the proper export settings or i was not impressed by the results... some had fixed default export setings, most had a lower video quality at the same filesize. ffmpeg allows me to set the -crf (18-24 usually) and -preset (veryslow, fast..) witch allows me to reduce the filesize drastically mantaining the same
  visible quality.

  Said that i’m using the preset at veryslow.(there is also placebo but the final video file is only 1% smaller in size).

  And here is the command i use

  ffmpeg
  
  -y //overwrite the file if it exists
  
  
  
  -i INPUTFILE // replace with the input file
  
  
  
  -metadata title=THETITLE // set a nice title, visible on modern devices
  
  -metadata date=THEDATE // set a nice title, visible on modern devices
  
  
  
  -c:v libx264 // use the h264 codec
  
   -crf 21 // try different numbers between 18-26
  
   -preset veryslow // placebo,slow,fast,ultrafast==big file 
  
   -tune film // tune it a little
  
   -pix_fmt yuv420p // preferred on most modern devices
  
   -profile:v main // preferred on most modern devices
  
   -level 3.1 // preferred on most modern devices 
  
   -refs 4 // preferred on most modern devices
  
  
  
  -c:a libfdk_aac // use aac
  
   -metadata:s:a language=eng // set a language, visible on modern devices 
  
   -b:a 128k // audio bitrate 128k is like mp3 192k
  
   -ar 48000 // 44100 ... whatever
  
   -ac 2 // audiochannels
  
   -movflags +faststart //move the metadata in the front of the video so it loads faster
  
  
  
  OUTPUTFILE

  some camcorder clips with m2ts already have the avc/h264 compatible codec so i just copy the stream.
  some have the ac3/dolby sorround audio. I convert the audio but keep the ac3 as second audio track mapping the ffmpeg streams.this allows me to watch the mp4 on browsers and mobile devices but i’m able to keep the surround sound to playback on some tv’s, advanced media players or devices like apple tv.

  not that i’m not happy with the speed (using quad core’s) but i recently read again about cuda opencl and there is also the simple fact that i’m not using other converters than ffmpeg since alot of time.

  Is ffmpeg (with the setting i use) a good converter to keep the same video quality than the source reducing the space occupied by and average of 30-40% ?

  Is GPU conversion really that bad (cuda .. testing a gtx970) ?
  it would be nice to add some more speed to the conversions by using both the gpu and the cpu..but for my understanding they cannot work together ??? and using only gpu is a drastical quality loss...cpu si more precise, gpu is faster in calculation are too imprecise from what i read.. so expensive softwares use cuda only for preview purpose... right ?

  Is ffmpeg or another software compatible with CPU+GPU encoding ?
  i really don’t remember where, but i read that the ffmpeg is not a good videoconverter.

  i’m really happy with the size/quality, i gained an average of 30% in space with no visible quality loss. With some extra parameters i can adjust some really old analog videos that are deinterlaced in a really bad way.

  maybe i could gain more size/quality with another software ???

  note : i like ffmpeg.it’s free and it has commandline so i can create my own interface with php html & js and use it on various machines without the need to install it in every device i use. i uplad the idevice clips directly to the ffmpeg server.

  btw. : explain the downvotes...

  EDIT :

  @talonmies ...cuda tag removed :

  http://www.nvidia.com/object/cuda_home_new.html

  CUDA® is a parallel computing platform and programming model invented
  by NVIDIA. It enables dramatic increases in computing performance by
  harnessing the power of the graphics processing unit (GPU). With
  millions of CUDA-enabled GPUs sold to date, software developers,
  scientists and researchers are finding broad-ranging uses for GPU
  computing with CUDA. Here are a few examples : - See more at :
  http://www.nvidia.com/object/cuda_home_new.html#sthash.dEYaqae7.dpuf

  isn’t cuda the programming model that a theoretical ffmpeg library should support to handle GPU encoding on nvidia cards like the gtx 970 ?? like the badaboom software http://www.geforce.com/games-applications/pc-applications/badaboom-media-converter.