[FFmpeg-devel] [PATCH] avformat/udp: Add a delay between packets for streaming to clients with short buffer

[Michael Niedermayer]

On Mon, Feb 29, 2016 at 10:40:02PM +0300, Pavel Nikiforov wrote:
> Hello !
> 
> This patch enables background sending of UDP packets with specified delay.
> When sending packets without a delay some devices with small RX buffer
> ( MAG200 STB, for example) will drop tail packets in burst causing
> decoding errors.
> 
> It needs to specify "fifo_size" with "packet_gap" .
> 
> The output url will looks like udp://xxx:yyy?fifo_size=<output fifo
> size>&packet_gap=<delay in usecs>
> 
> Patch attached.

>  udp.c |  133 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 129 insertions(+), 4 deletions(-)
> 80b57f176b5492070b2ed4853472de61b7d9ab7f  udp.patch
>  libavformat/udp.c | 133 ++++++++++++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 129 insertions(+), 4 deletions(-)
> 
> diff --git a/libavformat/udp.c b/libavformat/udp.c
> index ea80e52..ff676f4 100644
> --- a/libavformat/udp.c
> +++ b/libavformat/udp.c
> @@ -92,6 +92,7 @@ typedef struct UDPContext {
>      int circular_buffer_size;
>      AVFifoBuffer *fifo;
>      int circular_buffer_error;
> +    int packet_gap; /* delay between transmitted packets */
>  #if HAVE_PTHREAD_CANCEL
>      pthread_t circular_buffer_thread;
>      pthread_mutex_t mutex;
> @@ -112,6 +113,7 @@ typedef struct UDPContext {
>  #define E AV_OPT_FLAG_ENCODING_PARAM
>  static const AVOption options[] = {
>      { "buffer_size",    "System data size (in bytes)",                     OFFSET(buffer_size),    AV_OPT_TYPE_INT,    { .i64 = -1 },    -1, INT_MAX, .flags = D|E },
> +    { "packet_gap",     "Delay between packets, in usec",                  OFFSET(packet_gap),     AV_OPT_TYPE_INT,    { .i64 = 0  },     0, INT_MAX, .flags = E },

units should be seconds so that SI suffixes like for usecs work

also independant of this patch but supporting to transmit packets
at at their PCR/SCR/transmit time should be interresting


>      { "localport",      "Local port",                                      OFFSET(local_port),     AV_OPT_TYPE_INT,    { .i64 = -1 },    -1, INT_MAX, D|E },
>      { "local_port",     "Local port",                                      OFFSET(local_port),     AV_OPT_TYPE_INT,    { .i64 = -1 },    -1, INT_MAX, .flags = D|E },
>      { "localaddr",      "Local address",                                   OFFSET(localaddr),      AV_OPT_TYPE_STRING, { .str = NULL },               .flags = D|E },
> @@ -486,7 +488,7 @@ static int udp_get_file_handle(URLContext *h)
>  }
>  
>  #if HAVE_PTHREAD_CANCEL
> -static void *circular_buffer_task( void *_URLContext)
> +static void *circular_buffer_task_rx( void *_URLContext)
>  {
>      URLContext *h = _URLContext;
>      UDPContext *s = h->priv_data;

renaming things should be in a seperate patch

anyway, real review left to someone who knows th network stuff better
like nicolas

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

He who knows, does not speak. He who speaks, does not know. -- Lao Tsu
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 181 bytes
Desc: Digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20160301/26978555/attachment.sig>