Recherche avancée

Sur d’autres sites (8468)

• avformat/ty : Remove write-only array and variable

  11 août 2020, par Andreas Rheinhardt

  avformat/ty : Remove write-only array and variable
  Up until now, the TiVo demuxer parse an array of SEQ entries, yet it has
  
  never ever made any use of them. In fact, parse_master, the function
  
  parsing said table, only influenced the outside world in three ways : Via
  
  an excessive amount of error message in case a certain parameter is not
  
  what it expected ; via an allocation (the aforementioned write-only
  
  array) ; and by setting a certain parameter (ty->cur_chunk_pos), but that
  
  parameter is always overwritten before it is used (it is overwritten
  
  in get_chunk() on success and if get_chunk() fails, the error is
  
  returned to the caller anyway). So remove the array and the function
  
  used to parse it.
  Reviewed-by : Paul B Mahol <onemda@gmail.com>
  
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/ty.c

• Connecting to RTSP stream via FFMpeg - 'could not find codec parameters for stream 0'

  14 novembre 2013, par user2992545

  I'm a beginner in the FFMpeg world, so please excuse me my overall level of knowledge and any mistakes.

  What I have here is a DVR, made by ITX Security. I have an SDK for it and currently I'm trying to connect to its RTSP using FFMPEG. I've been partially succesfull (i think), the best what I got was :

  `(...)bin>ffplay -user-agent "ITX Security" rtsp://ADMIN:1234@192.168.2.130:5554/live/
  
  
  
  [rtsp @ 02a242e0] UDP timeout, retrying with TCPB sq=0B f=0/0
  
  [rtsp @ 02a242e0] method PAUSE failed: 501 Not Implemented
  
  [rtsp @ 02a242e0] Could not find codec parameters for stream 0 (Video: h264):unspecified size Consider increasing the value for the 'analyzeduration' and 'probesize' options
  
  rtsp://ADMIN:1234@192.168.2.130:5554/live/: could not find codec parameters
  
  
  
  nan:  0.000 fd=0 aq=    0KB vq=    0KB sq=    0B f=0/0`

  Is it really indicating that it has trouble in playing the stream (because it lacks a proper codec ?) - or am I just not getting the point ?

  I've captured traffic between my computer and the DVR in question, and something is happening (at least that's what Wireshark says).

  https://www.dropbox.com/s/j65lige244kg8jt/rtsp_ffmpeg.pcap

  What am I doing wrong ?

  Regards.

• ffmpeg ignores seg_duration with svt-av1

  25 décembre 2022, par Asav Mali

  I'm trying to convert a mp4 file containing a HEVC HDR10 stream to AV1 using SVT-AV1 with ffmpeg. For some reason the seg_duration parameter gets ignored :

  


  


  /usr/bin/ffmpeg -i "/tmp/VODProcessing/testclip.mp4" -map 0:0 -c:v
libsvtav1 -b:v 1048576 -maxrate:v 1101004 -bufsize 4194304 -vf
zscale=width=640:height=480 -svtav1-params
"tile-columns=0:tile-rows=0:scd=0:color-primaries=9:transfer-characteristics=16:matrix-coefficients=9:input-depth=10:fast-decode=1:mastering-display=G(0.265,0.69)B(0.15,0.06)R(0.68,0.32)WP(0.3127,0.329)L(4000.0,0.005):content-light=368,226:enable-hdr=1:color-range=1"
-pix_fmt yuv420p10le -color_trc smpte2084 -color_primaries bt2020 -colorspace bt2020nc -chroma_sample_location:v topleft -color_range:v pc -max_muxing_queue_size 1024 -preset 7 -bf 0 -force_key_frames
"expr:gte(t,n_forced*2)" -keyint_min 48 -use_timeline 1 -use_template
1 -map_metadata -1 -map_chapters -1 -f hls -seg_duration 4 -hls_time 4
-streaming 1 -hls_list_size 0 -hls_segment_filename "/tmp/VODProcessing/output/testclip/v-av01-480p-av01.0.12M.10_PQ/f-%04d.m4s"
-hls_fmp4_init_filename "init-v-av01-480p-av01.0.12M.10_PQ.m4s" -hls_segment_type fmp4 -hls_playlist_type vod -movflags frag_keyframe+frag_every_frame+write_colr+prefer_icc+skip_trailer+faststart
-hls_flags independent_segments -strict experimental "/tmp/VODProcessing/output/testclip/v-av01-480p-av01.0.12M.10_PQ/master.m3u8"

  


  


  Using a similar command and transcoding HEVC to HEVC works as expected and the segment duration is fine. Does this make any sense ? Checking the generated master.m3u8 file always gives me this for AV1 :

  


  #EXTM3U
#EXT-X-VERSION:7
#EXT-X-TARGETDURATION:7
#EXT-X-MEDIA-SEQUENCE:0
#EXT-X-PLAYLIST-TYPE:VOD
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-MAP:URI="init-v-av01-480p-av01.0.12M.10_PQ.m4s"
#EXTINF:6.715042,
f-0000.m4s
#EXTINF:6.715042,
f-0001.m4s
#EXTINF:6.715042,
f-0002.m4s
#EXTINF:6.715042,
f-0003.m4s
#EXTINF:6.715042,
f-0004.m4s
#EXTINF:6.715042,
f-0005.m4s
#EXTINF:6.715042,
f-0006.m4s
#EXTINF:6.715042,
f-0007.m4s
#EXTINF:6.715042,
f-0008.m4s
#EXTINF:6.715042,
f-0009.m4s
#EXTINF:6.715042,
f-0010.m4s
#EXTINF:6.715042,
f-0011.m4s
#EXTINF:6.715042,
f-0012.m4s
#EXTINF:6.715042,
f-0013.m4s
#EXTINF:6.715042,
f-0014.m4s
#EXTINF:6.715042,
f-0015.m4s
#EXTINF:0.583917,
f-0016.m4s
#EXT-X-ENDLIST


  


  As you can see, the segments are not 4 seconds long as defined in my command, they are 6.715042 seconds long, why that ???

  


  Thanks in advance