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• Skipping MP4 video

  4 avril 2017, par M.Yazdian

  I like to create the video player to show videos on my website. I made a video player in flash CS5 and actionscript3 to stream the videos on the website.

  My videos are often flv or mp4 format.
  In the flv files I use flvmdi app to inject the metadata to that ,and for skipping the flv file I use xmoov-php (video player can pass the keyframe number from flv metadat to xmoov-php to create the new flv file from passed keyframe to the last flv keyframe, and return the flv video file on the php header for flash video player to show the video ).

  but about mp4 format in Xmoov-php wiki it says :
  this file can’t support the mp4 format to skiping...!!!
  Now I need skiping the mp4 files in my video player (I like my viewers select a part of video before buffering all video on their browser and play it ).

  please give me a suggestion to skipping the mp4 file in the php or .net platform

• Hit noise when playing part of wave file with ALSA PCM interface

  11 décembre 2024, par wangt13

  I am working a WAVE file playing with ALSA PCM interface in Linux, and I heard noise when I played the file quickly and partially.

  


  Here is my playing function.

  


  static int playback_function(uint8_t *pcm_buf, int pcm_frames)
{
    int  rc;
    uint8_t *buf;
    int frame_size, sent;
    int periodsize;
    int left;

    frame_size = chan * av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
    periodsize = sys_periodsize; // 320 in my system
    buf = pcm_buf;
    left = pcm_frames;
    sent = 0;

    while (left > 0) {
        sent = (left > periodsize) ? periodsize : left;
        rc = snd_pcm_writei(pcm_handle, buf, sent);
        printf("rc: %d, sent: %d\n", rc, sent);
        if (rc == -EAGAIN || (rc >= 0 && (size_t)rc < sent)) {
            snd_pcm_wait(pcm_handle, 10);
        } else if (rc == -EPIPE) {
            snd_pcm_recover(pcm_handle, rc, 0);
        } else if (rc < 0) {
            break;
        }
        if (rc > 0) {
            left -= rc;
            buf += rc * frame_size;
        }
    }
    return rc;
}


  


  The pcm_buf and pcm_frames are got from swr_convert() in libswresample, in my case, the pcm_frames is 1187.

  


  By adding printf("rc: %d, sent: %d\n", rc, sent);, I got following logs.

  


  rc: 320, sent: 320
rc: 87, sent: 87
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103
rc: 320, sent: 320
rc: 320, sent: 320
rc: 87, sent: 87
rc: 320, sent: 320
rc: 320, sent: 320
rc: 103, sent: 103


  


  With above function, sometimes I can hear noise when playing the WAVE file quickly and repeatly.
  
So, how can I improve the WAVE playing without the noise ??

  


  I changed the above function by using filling 0 to the end of data buffer (to enforce silence).

  


  static int playback_test(uint8_t *pcm_buf, int pcm_frames)
{
    uint8_t *buf;
    int trd;
    int rc;
    int left;
    int frame_size, sent;
    int periodsize;
    int aligned = 0;

    frame_size = chan * av_get_bytes_per_sample(AV_SAMPLE_FMT_S16);
    periodsize = sys_periodsize; // 320 in my system

    buf = pcm_buf;
    left = pcm_frames;
    aligned = (left/periodsize + 1) * periodsize;
    memset(buf + left * frame_size, 0, (aligned - left) * frame_size);
    sent = 0;
///left = periodsize; // <== This causes more noise!!

    while (left > 0) {
        sent = (left > periodsize) ? periodsize : left;
        rc = snd_pcm_writei(pcm_handle, buf, sent);
        printf("rc: %d, sent: %d\n", rc, sent);
        if (rc == -EAGAIN || (rc >= 0 && (size_t)rc < sent)) {
            snd_pcm_wait(pcm_handle, 10);
        } else if (rc == -EPIPE) {
            snd_pcm_recover(pcm_handle, rc, 0);
        } else if (rc < 0) {
            break;
        }
        if (rc > 0) {
            left -= rc;
            buf += rc * frame_size;
        }
    }
    return rc;
}


  


  There is NO improvement as of the noise.

  


• Intel QuickSync error : Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height

  30 novembre 2018, par Arie Syamsudin

  I want to make IPTV with a topology like this :

  Restream / source -----> IPTV server -----> User

  The problem at the moment is the question of bandwidth that is still large.

  Finally I announced by IPTV software providers to transcode with Intel QuickSync video and FFmpeg.

  I followed the steps given by the software provider at the following link :
  http://www.ezhometech.com/document/intel_ffmpeg.txt

  Which comes from the link below :
  https://www.intel.com/content/dam/www/public/us/en/documents/white-paper...

  I installed IPTV software on a laptop with an Intel processor, chipset and VGA.

  [root@iptv ffmpeg-4.1]# **lspci**
  
  00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09)
  
  00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)
  
  00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04)
  
  00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05)
  
  00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05)
  
  00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5)
  
  00:1c.1 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 2 (rev b5)
  
  00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05)
  
  00:1f.0 ISA bridge: Intel Corporation HM65 Express Chipset Family LPC Controller (rev 05)
  
  00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family 6 port Mobile SATA AHCI Controller (rev 05)
  
  00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05)
  
  01:00.0 Ethernet controller: Qualcomm Atheros AR8152 v2.0 Fast Ethernet (rev c1)
  
  02:00.0 Network controller: Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
  
  
  
  [root@iptv ffmpeg-4.1]# **lspci -nn -s 0:02.0**
  
  00:02.0 VGA compatible controller [0300]: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09)

  but when I do a transcoding test, an error always appears :
  Error initializing output stream 0:0 — Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height.

  Error details :
  https://paste.fedoraproject.org/paste/vp9XIzbeOuyXRuLBlLfSng

  FFmpeg log :

  ./ffmpeg  -hwaccel qsv -i http://premium-play.org:8000/domm0H56Cj/q3ODLP6C16/2826 -vcodec h264_qsv -acodec copy -b:v 1200K -f mpegts udp://127.0.0.1:9011?pkt_size=1316
  
  ffmpeg version 3.2.12 Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 4.8.5 (GCC) 20150623 (Red Hat 4.8.5-28)
  
    configuration: --enable-libmfx --enable-nonfree
  
    libavutil      55. 34.101 / 55. 34.101
  
    libavcodec     57. 64.101 / 57. 64.101
  
    libavformat    57. 56.101 / 57. 56.101
  
    libavdevice    57.  1.100 / 57.  1.100
  
    libavfilter     6. 65.100 /  6. 65.100
  
    libswscale      4.  2.100 /  4.  2.100
  
    libswresample   2.  3.100 /  2.  3.100
  
  Input #0, mpegts, from 'http://premium-play.org:8000/domm0H56Cj/q3ODLP6C16/2826':
  
    Duration: N/A, start: 30200.274878, bitrate: N/A
  
    Program 1
  
      Metadata:
  
        service_name    : Service01
  
        service_provider: FFmpeg
  
      Stream #0:0[0x100]: Video: h264 (High) ([27][0][0][0] / 0x001B), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], 50 fps, 50 tbr, 90k tbn, 100 tbc
  
      Stream #0:1[0x101]: Audio: aac (LC) ([15][0][0][0] / 0x000F), 48000 Hz, stereo, fltp, 125 kb/s
  
  libva info: VA-API version 1.0.0
  
  libva info: va_getDriverName() returns 0
  
  libva info: User requested driver 'iHD'
  
  libva info: Trying to open /opt/intel/mediasdk/lib64/iHD_drv_video.so
  
  libva info: Found init function __vaDriverInit_1_0
  
  libva info: va_openDriver() returns 0
  
  [h264_qsv @ 0x2a89500] Selected ratecontrol mode is not supported by the QSV runtime. Choose a different mode.
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 (native) -> h264 (h264_qsv))
  
    Stream #0:1 -> #0:1 (copy)
  
  Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height