Recherche avancée

Sur d’autres sites (12421)

• lavfi/delogo : take SAR into account

  1er juillet 2013, par Jean Delvare

  lavfi/delogo : take SAR into account
  When interpolating, weights are based on relative distances, which
  
  assume square pixels. If a non-1:1 sample aspect ratio is used, it
  
  should be taken into account when comparing distances, because the
  
  human eye and brain care about the picture as it is displayed, not
  
  stored.
  Signed-off-by : Jean Delvare <khali@linux-fr.org>
  
  Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
  

  • [DH] libavfilter/vf_delogo.c

• ffmpeg transcode to hls and multiple aac audio tracks

  23 août 2023, par Aquarius

  I'm trying to transcode h264 mp4 file to HLS format with multiple AAC audio tracks. On Windows browsers everythins works like a shine. There's an option to switch audio track

  


  

  


  It doesn't work on Android devices or TV. On Android Opera browser video works with sound, but screen stuck while seeking and there's no option to switch audio track. On TV browser video works, it doesn't stuck when seeking but also no option to switch audio track

  


  Using video.js player on site. Below code for transcode and produced manifest file

  


  ffmpeg -i "file.mp4" -i PL-6ch.aac -i EN-6ch.aac -map 0:v -map 1:a -map 2:a -c:v copy -c:a:0 aac -ac:a:0 6 -af channelmap=channel_layout=5.1 -c:a:1 aac -ac:a:1 6 -af channelmap=channel_layout=5.1 -tag:v:0 h264 -b:v:0 2500k -tag:a:0 aac -b:a:0 384k -tag:a:1 aac -b:a:1 384k -f hls -hls_time 10 -hls_playlist_type vod -hls_list_size 0 -master_pl_name file.m3u8 -var_stream_map "v:0,agroup:AAC a:0,agroup:AAC,language:pl a:1,agroup:AAC,language:en" file_%v_.m3u8


  


  #EXTM3U
#EXT-X-VERSION:3
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="AAC",NAME="Polish",AUTOSELECT=YES,DEFAULT=YES,LANGUAGE="pl",URI="file_1_.m3u8"
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-ID="AAC",NAME="English",AUTOSELECT=YES,DEFAULT=NO,LANGUAGE="en",URI="file_2_.m3u8"
#EXT-X-STREAM-INF:PROGRAM-ID=1,BANDWIDTH=3172400,RESOLUTION=1920x872,CODECS="avc1.640029,mp4a.40.2",AUDIO="AAC" 
file_0_.m3u8

#EXT-X-STREAM-INF:BANDWIDTH=422400,CODECS="mp4a.40.2",AUDIO="AAC"
file_1_.m3u8

#EXT-X-STREAM-INF:BANDWIDTH=422400,CODECS="mp4a.40.2",AUDIO="AAC"
file_2_.m3u8


  


  Any clues what's wrong ?

  


• Pointers returned by xlib don't match any existing window IDs

  1er septembre 2022, par Kroltan

  I'm using some X11 bindings to query some window information and later pass it to FFmpeg. FFmpeg expects a "window ID" given in hexadecimal notation.

  


  This notation seems somewhat standard, as it is returned by programs like xwininfo or wmctrl. I haven't found much information about it, but it seems to just be the hexadecimal representation of the window pointer ? If I take the ID string given by these programs and give it to FFmpeg, it is able to capture the window correctly :

  


  $ xwininfo

xwininfo: Please select the window about which you
          would like information by clicking the
          mouse in that window.

xwininfo: Window id: 0x2800014 "Desktop — Plasma"

$ ffmpeg -f x11grab -window_id 0x2800014 -i :0+0,0 -f apng -vframes 1 out.png
# works fine


  


  However, if I try listing all the windows in code :

  


  var root = Window.None;
var parent = Window.None;
Xlib.XQueryTree(_display, Xlib.XDefaultRootWindow(_display), ref root, ref parent, out var children);

var ids = children
    .Select(ptr => $"0x{(ulong) ptr:x}")
    .ToArray();


  


  I don't see 0x2800014 in the results (even disregardingleading zeroes), and if I try running FFmpeg on one of those results, it fails terribly :

  


  $ ffmpeg -f x11grab -window_id 0x4400003 -i :0+0,0 -f apng -vframes 1

# snipped for brevity

Trailing option(s) found in the command: may be ignored.
[x11grab @ 0x55b811a8da40] Cannot get the image data event_error: response_type:0 error_code:8 sequence:10 resource_id:167772160 minor_code:4 major_code:130.
[x11grab @ 0x55b811a8da40] Continuing without shared memory.
[x11grab @ 0x55b811a8da40] Cannot get the image data event_error: response_type:0 error_code:8 sequence:11 resource_id:71303171 minor_code:0 major_code:73.
Input #0, x11grab, from ':0+0,0':
  Duration: N/A, bitrate: 38361 kb/s
  Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0, 200x200, 38361 kb/s, 29.97 fps, 1000k tbr, 1000k tbn
At least one output file must be specified


  


  So I must conclude my guess that they are hex pointers is incorrect, or that the Window type is not the pointer itself, but then the question stands, how can I get the actual window IDs so I can pass them to FFmpeg ?