ffmpeg hardware decoding issue on a rtsp h264 stream

Hi,

On an Odroid C2, I used to read IP camera stream with ffmpeg without HW decoding, as it was not available yet.

After reading many threads on this forum, regarding hw decoding  through ffmpeg, I decided to give a try....but without any success.

First of all, I tried to decode the Sintel.2010.720p.mkv file, and it worked well.

This is the command I used:

ffmpeg -c:v h264_v4l2m2m -i Sintel.2010.720p.mkv -an  -vf fps=1 -f image2 -strftime 1 "/dev/shm/cam1_%S.jpg"

(This takes a snapshot every second from the video file)

And I got this output:

[h264_v4l2m2m @ 0xaaaab68e84f0] driver 'meson-vdec' on card 'Amlogic Video Decoder'
[h264_v4l2m2m @ 0xaaaab68e84f0] Using device /dev/video0
[h264_v4l2m2m @ 0xaaaab68e84f0] driver 'meson-vdec' on card 'Amlogic Video Decoder'
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (h264_v4l2m2m) -> mjpeg (native))
Press [q] to stop, [?] for help
[h264_v4l2m2m @ 0xaaaab68e84f0] output  POLLERR
[swscaler @ 0xaaaab691f000] deprecated pixel format used, make sure you did set range correctly
Output #0, image2, to '/dev/shm/cam1_%S.jpg':
  Metadata:
    encoder         : Lavf57.83.100
    Chapter #0:0: start 0.000000, end 103.125000
    Metadata:
      title           : Chapter 01
    Chapter #0:1: start 103.125000, end 148.667000
    Metadata:
      title           : Chapter 02
    Chapter #0:2: start 148.667000, end 349.792000
    Metadata:
      title           : Chapter 03
    Chapter #0:3: start 349.792000, end 437.208000
    Metadata:
      title           : Chapter 04
    Chapter #0:4: start 437.208000, end 472.075000
    Metadata:
      title           : Chapter 05
    Chapter #0:5: start 472.075000, end 678.833000
    Metadata:
      title           : Chapter 06
    Chapter #0:6: start 678.833000, end 744.083000
    Metadata:
      title           : Chapter 07
    Chapter #0:7: start 744.083000, end 888.032000
    Metadata:
      title           : Chapter 08
    Stream #0:0(eng): Video: mjpeg, yuvj420p(pc), 1280x544 [SAR 1:1 DAR 40:17], q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc
    Metadata:
      encoder         : Lavc57.107.100 mjpeg
    Side data:
      cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
frame=   53 fps=3.4 q=4.8 Lsize=N/A time=00:00:53.00 bitrate=N/A speed=3.44x

After that successfull test, I tried this from a CCTV RTSP stream :

ffmpeg -stimeout 5000000 -c:v h264_v4l2m2m -i rtsp://192.168.1.31/11 -an  -vf fps=1 -f image2 -strftime 1 "/dev/shm/cam1_%S.jpg"

and I got this output:

[h264 @ 0xaaaadbc04330] corrupted macroblock 16 36 (total_coeff=-1)
[h264 @ 0xaaaadbc04330] error while decoding MB 16 36
[h264 @ 0xaaaadbc04330] concealing 753 DC, 753 AC, 753 MV errors in I frame
Guessed Channel Layout for Input Stream #0.1 : mono
Input #0, rtsp, from 'rtsp://192.168.1.31/11':
  Metadata:
    title           : 10
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: h264 (Baseline), yuvj420p(pc, bt709, progressive), 1280x720, 2.08 tbr, 90k tbn, 180k tbc
    Stream #0:1: Audio: pcm_alaw, 8000 Hz, mono, s16, 64 kb/s
[h264_v4l2m2m @ 0xaaaadbd68c70] driver 'meson-vdec' on card 'Amlogic Video Decoder'
[h264_v4l2m2m @ 0xaaaadbd68c70] Using device /dev/video0
[h264_v4l2m2m @ 0xaaaadbd68c70] driver 'meson-vdec' on card 'Amlogic Video Decoder'
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (h264_v4l2m2m) -> mjpeg (native))
Press [q] to stop, [?] for help
[h264_v4l2m2m @ 0xaaaadbd68c70] output  POLLERR
[swscaler @ 0xaaaadbc47f60] deprecated pixel format used, make sure you did set range correctly
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp.
Output #0, image2, to '/dev/shm/cam1_%S.jpg':
  Metadata:
    title           : 10
    encoder         : Lavf57.83.100
    Stream #0:0: Video: mjpeg, yuvj420p(pc), 1280x720, q=2-31, 200 kb/s, 1 fps, 1 tbn, 1 tbc
    Metadata:
      encoder         : Lavc57.107.100 mjpeg
    Side data:
      cpb: bitrate max/min/avg: 0/0/200000 buffer size: 0 vbv_delay: -1
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
[Parsed_fps_0 @ 0xaaaadbc668a0] Discarding initial frame(s) with no timestamp. 
    Last message repeated 1 times
frame=    0 fps=0.0 q=0.0 Lsize=N/A time=00:00:00.00 bitrate=N/A speed=   0x    
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)

I am using the regular ffmpeg, installed through apt install.

(No compilation from source).

I am using the latest armbian ubuntu stable version:

4.19.20-meson64 #5.75 SMP PREEMPT Fri Feb 8 10:08:40 CET 2019 aarch64 aarch64 aarch64 GNU/Linux

Any sugestions for using HW decoding over a RTSP stream?

Thx

Fabian