Recherche avancée

Sur d’autres sites (18642)

• lavc/h263dsp : R-V V {h,v}_loop_filter

  19 mai 2024, par Rémi Denis-Courmont

  lavc/h263dsp : R-V V h,v_loop_filter
  Since the horizontal and vertical filters are identical except for a
  
  transposition, this uses a common subprocedure with an ad-hoc ABI.
  
  To preserve return-address stack prediction, a link register has to be
  
  used (c.f. the "Control Transfer Instructions" from the
  
  RISC-V ISA Manual). The alternate/temporary link register T0 is used
  
  here, so that the normal RA is preserved (something Arm cannot do !).
  To load the strength value based on `qscale`, the shortest possible
  
  and PIC-compatible sequence is used : AUIPC ; ADD ; LBU. The classic
  
  LLA ; ADD ; LBU sequence would add one more instruction since LLA is a
  
  convenience alias for AUIPC ; ADDI. To ensure that this trick works,
  
  relocation relaxation is disabled.
  To implement the two signed divisions by a power of two toward zero :
  
   (x / (1 << SHIFT))
  
  the code relies on the small range of integers involved, computing :
  
   (x + (x >> (16 - SHIFT))) >> SHIFT
  
  rather than the more general :
  
   (x + ((x >> (16 - 1)) & ((1 << SHIFT) - 1))) >> SHIFT
  
  Thus one ANDI instruction is avoided.
  T-Head C908 :
  
  h263dsp.h_loop_filter_c :       228.2
  
  h263dsp.h_loop_filter_rvv_i32 : 144.0
  
  h263dsp.v_loop_filter_c :       242.7
  
  h263dsp.v_loop_filter_rvv_i32 : 114.0
  
  (C is probably worse in real use due to less predictible branches.)
  

  • [DH] libavcodec/h263dsp.c
  • [DH] libavcodec/h263dsp.h
  • [DH] libavcodec/riscv/Makefile
  • [DH] libavcodec/riscv/h263dsp_init.c
  • [DH] libavcodec/riscv/h263dsp_rvv.S

• FFMPEG tee muxer giving "Output file #0 does not contain any stream"

  31 août 2020, par Giorgi Aptsiauri

  I am trying to create two streams : one is mpegts UDP stream another - rtmp to Twitch servers.

  


  This command works :

  


    ffmpeg -threads:v 2 -threads:a 16 -filter_threads 2 -thread_queue_size 16 -y \
 -f dshow -video_size 1920x1080 -pixel_format uyvy422 -framerate 25 -rtbufsize 500M -i video="Decklink Video Capture" \
 -f dshow -rtbufsize 100M -i audio="Decklink Audio Capture" \
 -preset ultrafast -c:v libx264 -tune zerolatency -b:v 900k -map 0:v:0 -f mpegts udp://127.0.0.1:5555 \ 
 -pix_fmt yuv420p -c:v libx264 -crf 20 -tune zerolatency -f flv rtmp://live-fra05.twitch.tv/app/stream_key


  


  But it requires double the encoding CPU power.

  


  So, following this, I rewrote the command like this :

  


  ffmpeg -threads:v 2 -threads:a 16 -filter_threads 2 -thread_queue_size 16 -y \
 -f dshow -video_size 1920x1080 -pixel_format uyvy422 -framerate 25 -rtbufsize 500M -i video="Decklink Video Capture" \
 -f dshow -rtbufsize 100M -i audio="Decklink Audio Capture" \
 -preset ultrafast -c:v libx264 -tune zerolatency -b:v 900k \
 -f tee "[select=\'0:v:0\':f=mpegts]udp://127.0.0.1:5555|[select=\'0:v:0,1:a:0\':f=flv]rtmp://live-fra05.twitch.tv/app/stream_key"


  


  By writing -f tee "[select=\'0:v:0\':f=mpegts]udp://127.0.0.1:5555|[select=\'0:v:0,1:a:0\':f=flv]rtmp://live-fra05.twitch.tv/app/stream_key", I mean :

  


  

  • create UDP stream at udp ://127.0.0.1:5555 and only include video stream from "Decklink Video Capture"

  


  • create RTMP stream where we include the same video stream as above and also the audio stream from "Decklink Audio Capture"

  


  


  I get the error message :

  


  Output file #0 does not contain any stream


  


  How do I fix this ? I assume I made a mistake in the command.

  


• Video from images to mp4 in nvidia GPU

  16 août 2019, par M.y

  I am trying to encode a h264 .mp4 video created from .jpg images using a 1070ti nvidia cuda power, having a a crossfade transition between each image.
  I am able to render the video in GPU using the flags -c:v h264_nvenc, I see a short peak in the GPU encoding, but with a long period of computer CPU hight load, I guess preparing the transitioning images. But the image preparation it happens on cpu/ram due the -filter_complex and is quite slow.
  This works :

  ffmpeg.exe, -y, -loop, 1, -t, 2.5, -i, 1565957420594_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565957453659_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565957487743_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565957525280_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565957587308_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565957644898_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565957859119_labeled.jpg, -loop, 1, -t, 2.5, -i,1565959133561_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565959412948_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565959501884_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565959755432_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565959882380_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565960023185_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565960157174_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565960683303_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565961151548_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565961230278_labeled.jpg, -loop, 1, -t, 2.5, -i, 1565961671766_labeled.jpg, -loop, 1, -t, 2.5, -i, final.jpg, -loop, 1, -t, 2.5, -i, final.jpg, -c:v, h264_nvenc, -preset, fast, -filter_complex, [1]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+0.5/TB[f0];[2]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+1.0/TB[f1];[3]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+1.5/TB[f2];[4]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+2.0/TB[f3];[5]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+2.5/TB[f4];[6]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+3.0/TB[f5];[7]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+3.5/TB[f6];[8]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+4.0/TB[f7];[9]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+4.5/TB[f8];[10]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+5.0/TB[f9];[11]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+5.5/TB[f10];[12]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+6.0/TB[f11];[13]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+6.5/TB[f12];[14]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+7.0/TB[f13];[15]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+7.5/TB[f14];[16]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+8.0/TB[f15];[17]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+8.5/TB[f16];[18]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+9.0/TB[f17];[19]fade=d=0.5:t=in:alpha=1,setpts=PTS-STARTPTS+9.5/TB[f18];[0][f0]overlay[bg1];[bg1][f1]overlay[bg2];[bg2][f2]overlay[bg3];[bg3][f3]overlay[bg4];[bg4][f4]overlay[bg5];[bg5][f5]overlay[bg6];[bg6][f6]overlay[bg7];[bg7][f7]overlay[bg8];[bg8][f8]overlay[bg9];[bg9][f9]overlay[bg10];[bg10][f10]overlay[bg11];[bg11][f11]overlay[bg12];[bg12][f12]overlay[bg13];[bg13][f13]overlay[bg14];[bg14][f14]overlay[bg15];[bg15][f15]overlay[bg16];[bg16][f16]overlay[bg17];[bg17][f17]overlay[bg18];[bg18][f18]overlay[v], -map, [v], -movflags, +faststart, output.mp4

  I am trying to do all work in the GPU, theoretically I can encode all images in GPU memory using in each -i the flags "-hwaccel cuvid -c:v mjpeg_cuvid" I receive the following error :

  [mjpeg_cuvid @ 00000000024ef980] ignoring invalid SAR: 0/0
  
  Impossible to convert between the formats supported by the filter 'graph 0 input from stream 1:0' and the filter 'auto_scaler_0'
  
  Error reinitializing filters!
  
  Failed to inject frame into filter network: Function not implemented
  
  Error while processing the decoded data for stream #0:0

  Is there a way to load images in the GPU with the "fade" flag applied ?

  Thanks in advance !