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FFmpeg/libavformat/rtpdec_vc2hq.c
Carl Eugen Hoyos dc77e64f2d lavf/rtpdec*: Constify all RTPDynamicProtocolHandler.
Reviewed-by: Muhammad Faiz
2018-02-14 01:14:35 +01:00

226 lines
7.4 KiB
C

/*
* RTP parser for VC-2 HQ payload format (draft version 1) - experimental
* Copyright (c) 2016 Thomas Volkert <thomas@netzeal.de>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/intreadwrite.h"
#include "libavcodec/dirac.h"
#include "avio_internal.h"
#include "rtpdec_formats.h"
#define RTP_VC2HQ_PL_HEADER_SIZE 4
#define DIRAC_DATA_UNIT_HEADER_SIZE 13
#define DIRAC_PIC_NR_SIZE 4
#define DIRAC_RTP_PCODE_HQ_PIC_FRAGMENT 0xEC
struct PayloadContext {
AVIOContext *buf;
uint32_t frame_size;
uint32_t frame_nr;
uint32_t timestamp;
uint32_t last_unit_size;
int seen_sequence_header;
};
static const uint8_t start_sequence[] = { 'B', 'B', 'C', 'D' };
static void fill_parse_info_header(PayloadContext *pl_ctx, uint8_t *buf,
uint8_t parse_code, uint32_t data_unit_size)
{
memcpy(buf, start_sequence, sizeof(start_sequence));
buf[4] = parse_code;
AV_WB32(&buf[5], data_unit_size);
AV_WB32(&buf[9], pl_ctx->last_unit_size);
pl_ctx->last_unit_size = data_unit_size;
}
static int vc2hq_handle_sequence_header(PayloadContext *pl_ctx, AVStream *st, AVPacket *pkt,
const uint8_t *buf, int len)
{
int res;
uint32_t size = DIRAC_DATA_UNIT_HEADER_SIZE + len;
if ((res = av_new_packet(pkt, DIRAC_DATA_UNIT_HEADER_SIZE + len)) < 0)
return res;
fill_parse_info_header(pl_ctx, pkt->data, 0x00, size);
/* payload of seq. header */
memcpy(pkt->data + DIRAC_DATA_UNIT_HEADER_SIZE, buf, len);
pkt->stream_index = st->index;
pl_ctx->seen_sequence_header = 1;
return 0;
}
static int vc2hq_mark_end_of_sequence(PayloadContext *pl_ctx, AVStream *st, AVPacket *pkt)
{
int res;
uint32_t size = 0;
/* create A/V packet */
if ((res = av_new_packet(pkt, DIRAC_DATA_UNIT_HEADER_SIZE)) < 0)
return res;
fill_parse_info_header(pl_ctx, pkt->data, 0x10, size);
pkt->stream_index = st->index;
pl_ctx->seen_sequence_header = 0;
return 0;
}
static int vc2hq_handle_frame_fragment(AVFormatContext *ctx, PayloadContext *pl_ctx, AVStream *st,
AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len,
int flags)
{
int res;
uint32_t pic_nr;
uint16_t frag_len;
uint16_t no_slices;
/* sanity check for size of input packet: 16 bytes header in any case as minimum */
if (len < 16) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len);
return AVERROR_INVALIDDATA;
}
pic_nr = AV_RB32(&buf[4]);
frag_len = AV_RB16(&buf[12]);
no_slices = AV_RB16(&buf[14]);
if (pl_ctx->buf && pl_ctx->frame_nr != pic_nr) {
av_log(ctx, AV_LOG_WARNING, "Dropping buffered RTP/VC2hq packet fragments - non-continuous picture numbers\n");
ffio_free_dyn_buf(&pl_ctx->buf);
}
/* transform parameters? */
if (no_slices == 0) {
if (len < frag_len + 16) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len);
return AVERROR_INVALIDDATA;
}
/* start frame buffering with new dynamic buffer */
if (!pl_ctx->buf) {
res = avio_open_dyn_buf(&pl_ctx->buf);
if (res < 0)
return res;
/* reserve memory for frame header */
res = avio_seek(pl_ctx->buf, DIRAC_DATA_UNIT_HEADER_SIZE + DIRAC_PIC_NR_SIZE, SEEK_SET);
if (res < 0)
return res;
pl_ctx->frame_nr = pic_nr;
pl_ctx->timestamp = *timestamp;
pl_ctx->frame_size = DIRAC_DATA_UNIT_HEADER_SIZE + DIRAC_PIC_NR_SIZE;
}
avio_write(pl_ctx->buf, buf + 16 /* skip pl header */, frag_len);
pl_ctx->frame_size += frag_len;
return AVERROR(EAGAIN);
} else {
if (len < frag_len + 20) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len);
return AVERROR_INVALIDDATA;
}
/* transform parameters were missed, no buffer available */
if (!pl_ctx->buf)
return AVERROR_INVALIDDATA;
avio_write(pl_ctx->buf, buf + 20 /* skip pl header */, frag_len);
pl_ctx->frame_size += frag_len;
/* RTP marker bit means: last fragment of current frame was received;
otherwise, an additional fragment is needed for the current frame */
if (!(flags & RTP_FLAG_MARKER))
return AVERROR(EAGAIN);
}
/* close frame buffering and create A/V packet */
res = ff_rtp_finalize_packet(pkt, &pl_ctx->buf, st->index);
if (res < 0)
return res;
fill_parse_info_header(pl_ctx, pkt->data, DIRAC_PCODE_PICTURE_HQ, pl_ctx->frame_size);
AV_WB32(&pkt->data[13], pl_ctx->frame_nr);
pl_ctx->frame_size = 0;
return 0;
}
static int vc2hq_handle_packet(AVFormatContext *ctx, PayloadContext *pl_ctx,
AVStream *st, AVPacket *pkt, uint32_t *timestamp,
const uint8_t *buf, int len, uint16_t seq,
int flags)
{
uint8_t parse_code = 0;
int res = 0;
if (pl_ctx->buf && pl_ctx->timestamp != *timestamp) {
av_log(ctx, AV_LOG_WARNING, "Dropping buffered RTP/VC2hq packet fragments - non-continuous timestamps\n");
ffio_free_dyn_buf(&pl_ctx->buf);
pl_ctx->frame_size = 0;
}
/* sanity check for size of input packet: needed header data as minimum */
if (len < RTP_VC2HQ_PL_HEADER_SIZE) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/VC2hq packet, got %d bytes\n", len);
return AVERROR_INVALIDDATA;
}
parse_code = buf[3];
/* wait for next sequence header? */
if (pl_ctx->seen_sequence_header || parse_code == DIRAC_PCODE_SEQ_HEADER) {
switch(parse_code) {
/* sequence header */
case DIRAC_PCODE_SEQ_HEADER:
res = vc2hq_handle_sequence_header(pl_ctx, st, pkt, buf + RTP_VC2HQ_PL_HEADER_SIZE, len - RTP_VC2HQ_PL_HEADER_SIZE);
break;
/* end of sequence */
case DIRAC_PCODE_END_SEQ:
res = vc2hq_mark_end_of_sequence(pl_ctx, st, pkt);
break;
/* HQ picture fragment */
case DIRAC_RTP_PCODE_HQ_PIC_FRAGMENT:
res = vc2hq_handle_frame_fragment(ctx, pl_ctx, st, pkt, timestamp, buf, len, flags);
break;
}
}
return res;
}
const RTPDynamicProtocolHandler ff_vc2hq_dynamic_handler = {
.enc_name = "VC2",
.codec_type = AVMEDIA_TYPE_VIDEO,
.codec_id = AV_CODEC_ID_DIRAC,
.priv_data_size = sizeof(PayloadContext),
.parse_packet = vc2hq_handle_packet
};