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• aarch64 : Add NEON optimizations for 10 and 12 bit vp9 loop filter

  5 janvier 2017, par Martin Storsjö

  aarch64 : Add NEON optimizations for 10 and 12 bit vp9 loop filter
  This work is sponsored by, and copyright, Google.
  This is similar to the arm version, but due to the larger registers
  
  on aarch64, we can do 8 pixels at a time for all filter sizes.
  Examples of runtimes vs the 32 bit version, on a Cortex A53 :
  
                                               ARM AArch64
  
  vp9_loop_filter_h_4_8_10bpp_neon :          213.2   172.6
  
  vp9_loop_filter_h_8_8_10bpp_neon :          281.2   244.2
  
  vp9_loop_filter_h_16_8_10bpp_neon :         657.0   444.5
  
  vp9_loop_filter_h_16_16_10bpp_neon :       1280.4   877.7
  
  vp9_loop_filter_mix2_h_44_16_10bpp_neon :   397.7   358.0
  
  vp9_loop_filter_mix2_h_48_16_10bpp_neon :   465.7   429.0
  
  vp9_loop_filter_mix2_h_84_16_10bpp_neon :   465.7   428.0
  
  vp9_loop_filter_mix2_h_88_16_10bpp_neon :   533.7   499.0
  
  vp9_loop_filter_mix2_v_44_16_10bpp_neon :   271.5   244.0
  
  vp9_loop_filter_mix2_v_48_16_10bpp_neon :   330.0   305.0
  
  vp9_loop_filter_mix2_v_84_16_10bpp_neon :   329.0   306.0
  
  vp9_loop_filter_mix2_v_88_16_10bpp_neon :   386.0   365.0
  
  vp9_loop_filter_v_4_8_10bpp_neon :          150.0   115.2
  
  vp9_loop_filter_v_8_8_10bpp_neon :          209.0   175.5
  
  vp9_loop_filter_v_16_8_10bpp_neon :         492.7   345.2
  
  vp9_loop_filter_v_16_16_10bpp_neon :        951.0   682.7
  This is significantly faster than the ARM version in almost
  
  all cases except for the mix2 functions.
  Based on START_TIMER/STOP_TIMER wrapping around a few individual
  
  functions, the speedup vs C code is around 2-3x.
  Signed-off-by : Martin Storsjö <martin@martin.st>
  

  • [DH] libavcodec/aarch64/Makefile
  • [DH] libavcodec/aarch64/vp9dsp_init_16bpp_aarch64_template.c
  • [DH] libavcodec/aarch64/vp9lpf_16bpp_neon.S

• Moviepy has issues when concatenating ImageClips of different dimensions

  22 mars 2021, par Lysander Cox

  Example of the issues : https://drive.google.com/file/d/1WxfYtDTD0kc_4WQzzvB6QXkZWo-e2Vuk/view?usp=sharing

  


  Here's the code that led to the issue :

  


  def fragmentConcat(comment, filePrefix):
    finalClips = []
    dirName = filePrefix + comment['id']
    vidClips = [mpy.VideoFileClip(dirName + '/' + file) for file 
                in natsorted(os.listdir(dirName))]
    
    finalClip = mpy.concatenate_videoclips(vidClips, method = "compose")
    finalClips.append(finalClip)
    
    if 'replies' in comment:
        for reply in comment['replies']:
            finalClips += fragmentConcat(reply, filePrefix)
            
    return finalClips

def finalVideoMaker(thread):
    fragmentGen(thread)
    filePrefix = thread['id'] + '/videos/'

    #Clips of comments and their children being read aloud.
    commentClips = []

    for comment in thread['comments']:
        commentClipFrags = fragmentConcat(comment, filePrefix)
        commentClip = mpy.concatenate_videoclips(commentClipFrags, method = "compose")
        commentClips.append(commentClip)

        #1 second of static to separate clips.
        staticVid = mpy.VideoFileClip('assets/static.mp4')
        commentClips.append(staticVid)

    finalVid = mpy.concatenate_videoclips(commentClips)
    finalVid.write_videofile(thread['id'] + '/final.mp4')


  


  I'm certain that these issues appear somewhere in here, because the individual video "fragments" (which are concatenated here) do not exhibit the issue with the clip I showed.

  


  I have tried adding and removing the method = "compose" parameter. It does not seem to have an affect. How can I resolve this ? Thanks.

  


• Master playlist generate points to only one resolution among multiple

  25 avril 2019, par Parthib Dutta

  I am trying to convert one mp4 movie to multiple bitrate HLS . The individual resolutions are generating fine with their own playlists . But the master playlist includes only one resolution .

  ffmpeg -hide_banner -re -i video.mp4 -master_pl_name master.m3u8    ^
  
    -vf scale=w=640:h=-2 -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4   -b:v 800k -maxrate 856k -bufsize 1200k -b:a 96k -hls_segment_filename D:\xampp\htdocs\streaming-demo\360p_%%03d.ts  D:\xampp\htdocs\streaming-demo\360p_%v.m3u8 ^
  
    -vf scale=w=842:h=-2 -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4  -b:v 1400k -maxrate 1498k -bufsize 2100k -b:a 128k -hls_segment_filename D:\xampp\htdocs\streaming-demo\480p_%%03d.ts  D:\xampp\htdocs\streaming-demo\480p_%v.m3u8 ^
  
    -vf scale=w=1280:h=-2 -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4  -b:v 2800k -maxrate 2996k -bufsize 4200k -b:a 128k -hls_segment_filename D:\xampp\htdocs\streaming-demo\720p_%%03d.ts  D:\xampp\htdocs\streaming-demo\720p_%v.m3u8 ^
  
    -vf scale=w=1920:h=-2 -c:a aac -ar 48000 -c:v h264 -profile:v main -crf 20 -sc_threshold 0 -g 48 -keyint_min 48 -hls_time 4  -b:v 5000k -maxrate 5350k -bufsize 7500k -b:a 192k -hls_segment_filename D:\xampp\htdocs\streaming-demo\1080p_%%03d.ts  D:\xampp\htdocs\streaming-demo\1080p_%v.m3u8

  It include only the 360p resolution playlist link .