On 20/07/14 13:55, wm4 wrote:
> On Sat, 19 Jul 2014 19:21:47 -0400
> siret...@gmail.com wrote:
>
>> From: John Peterson <john.peters...@hotmail.com>
>>
>> Useful to simulate low performance input.
>> The minimum resolution is 1 Kib/s.
>>
>> The input stream packet size setting can be used to test the performance
>> with different packet sizes at the maximum or simulated maximum input
>> rate.
>> ---
>> libavformat/avio.h | 15 ++++++++++++
>> libavformat/aviobuf.c | 63
>> +++++++++++++++++++++++++++++++++++++++++++++++++++
>> libavformat/utils.c | 5 +++-
>> 3 files changed, 82 insertions(+), 1 deletion(-)
>>
>> diff --git a/libavformat/avio.h b/libavformat/avio.h
>> index 3360e82..b16fd00 100644
>> --- a/libavformat/avio.h
>> +++ b/libavformat/avio.h
>> @@ -54,6 +54,19 @@ typedef struct AVIOInterruptCB {
>> } AVIOInterruptCB;
>>
>> /**
>> + * Input stream throttle queue.
>> + */
>> +typedef struct traffic {
>> + int64_t time;
>> + int traf;
>> +} traffic;
>> +typedef struct traffic_queue {
>> + int size;
>> + int len;
>> + traffic *data;
>> +} traffic_queue;
>> +
>> +/**
>> * Bytestream IO Context.
>> * New fields can be added to the end with minor version bumps.
>> * Removal, reordering and changes to existing fields require a major
>> @@ -96,6 +109,8 @@ typedef struct AVIOContext {
>> int eof_reached; /**< true if eof reached */
>> int write_flag; /**< true if open for writing */
>> int max_packet_size;
>> + int throttle; /**< command line argument throttle */
>> + traffic_queue t_queue; /**< traffic queue for throttle */
>> unsigned long checksum;
>> unsigned char *checksum_ptr;
>> unsigned long (*update_checksum)(unsigned long checksum, const uint8_t
>> *buf, unsigned int size);
>> diff --git a/libavformat/aviobuf.c b/libavformat/aviobuf.c
>> index cc79146..f957625 100644
>> --- a/libavformat/aviobuf.c
>> +++ b/libavformat/aviobuf.c
>> @@ -30,8 +30,10 @@
>> #include "internal.h"
>> #include "url.h"
>> #include <stdarg.h>
>> +#include <unistd.h>
>>
>> #define IO_BUFFER_SIZE 32768
>> +#define INPUT_HISTORY_SIZE 10 // s
>>
>> /**
>> * Do seeks within this distance ahead of the current buffer by skipping
>> @@ -51,7 +53,11 @@ static const AVClass *ffio_url_child_class_next(const
>> AVClass *prev)
>> return prev ? NULL : &ffurl_context_class;
>> }
>>
>> +#define OFFSET(x) offsetof(AVIOContext, x)
>> +#define D AV_OPT_FLAG_DECODING_PARAM
>> static const AVOption ffio_url_options[] = {
>> + { "in_packet_size", "set max input packet size",
>> OFFSET(max_packet_size), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, D },
>> + { "throttle", "set max input rate in Kib/s", OFFSET(throttle),
>> AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, D },
>> { NULL },
>> };
>>
>> @@ -359,6 +365,57 @@ void avio_wb24(AVIOContext *s, unsigned int val)
>>
>> /* Input stream */
>>
>> +/* traffic history for input throttle */
>> +static void t_queue_push(traffic_queue *queue, int64_t time, int traf)
>> +{
>> + traffic* data;
>> + queue->len++;
>> + data = av_realloc(queue->data, sizeof(traffic)*queue->len);
>> + if (!data)
>> + return;
>> + queue->data = data;
>> + queue->data[queue->len-1].time = time;
>> + queue->data[queue->len-1].traf = traf;
>> +}
>> +
>> +static void t_queue_pop(traffic_queue *queue)
>> +{
>> + int i;
>> + for (i = 0; i < queue->len; i++) {
>> + if (queue->data[i].time < av_gettime()-INPUT_HISTORY_SIZE*1000000) {
>> + memmove(queue->data + i, queue->data + i + 1,
>> sizeof(traffic)*(queue->len - i - 1));
>> + queue->len--;
>> + }
>> + }
>> +}
>> +
>> +/* input throttle */
>> +static int64_t avio_throttle_rate(traffic_queue *queue, int64_t time)
>> +{
>> + int64_t sum = 0;
>> + int i;
>> + for (i = 0; i < queue->len; i++) {
>> + if (queue->data[i].time > av_gettime()-time)
>> + sum += queue->data[i].traf;
>> + }
>> + return (double)sum/((double)time/1000000.0); // B/s
>> +}
>> +
>> +static int avio_throttle(AVIOContext *s)
>> +{
>> + if (!s->throttle) return 0;
>> + t_queue_pop(&s->t_queue);
>> + // measure speed at multiple intervals to create an even transfer rate
>> + if (avio_throttle_rate(&s->t_queue, 0.001*1000000) > s->throttle*0x80
>> + || avio_throttle_rate(&s->t_queue, 0.01*1000000) > s->throttle*0x80
>> + || avio_throttle_rate(&s->t_queue, 0.1*1000000) > s->throttle*0x80
>> + || avio_throttle_rate(&s->t_queue, 1*1000000) > s->throttle*0x80
>> + || avio_throttle_rate(&s->t_queue, 10*1000000) > s->throttle*0x80
>> + )
>> + return 1;
>> + return 0;
>> +}
>> +
>> static void fill_buffer(AVIOContext *s)
>> {
>> uint8_t *dst = !s->max_packet_size &&
>> @@ -405,6 +462,12 @@ static void fill_buffer(AVIOContext *s)
>> s->pos += len;
>> s->buf_ptr = dst;
>> s->buf_end = dst + len;
>> +
>> + // throttle
>> + t_queue_push(&s->t_queue, av_gettime(), len);
>> + while (s->throttle && avio_throttle(s)) {
>> + usleep(0.1*1000000);
>> + }
>> }
>> }
>>
>> diff --git a/libavformat/utils.c b/libavformat/utils.c
>> index 7a054af..2211b9c 100644
>> --- a/libavformat/utils.c
>> +++ b/libavformat/utils.c
>> @@ -427,8 +427,11 @@ int avformat_open_input(AVFormatContext **ps, const
>> char *filename,
>> }
>>
>> /* e.g. AVFMT_NOFILE formats will not have a AVIOContext */
>> - if (s->pb)
>> + if (s->pb) {
>> ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
>> + if ((ret = av_opt_set_dict(s->pb, &tmp)) < 0)
>> + goto fail;
>> + }
>>
>> if (s->iformat->read_header)
>> if ((ret = s->iformat->read_header(s)) < 0)
>
> I'd say no. Useful for debugging sometimes (or is there a real
> usecase???), but does it really have to be in the main repo? Also, this
> should be implemented as nested protocol, not somehow hacking it into
> aviobuf.c.
As protocol would be surely _much_ easier to use IMHO.
lu
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