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ffmpeg/libavformat/rtpdec_jpeg.c
Michael Niedermayer bff2afb3e9 Merge remote-tracking branch 'qatar/master' 
* qatar/master:
  x86: dsputil: Only compile motion_est code when encoders are enabled
  mem: fix typo in check for __ICC
  fate: mp3: drop redundant CMP setting
  rtp: Depacketization of JPEG (RFC 2435)
  Rename ff_put_string to avpriv_put_string
  mjpeg: Rename some symbols to avpriv_* instead of ff_*
  yadif: cosmetics

Conflicts:
	Changelog
	libavcodec/mjpegenc.c
	libavcodec/x86/Makefile
	libavfilter/vf_yadif.c
	libavformat/version.h
	libavutil/mem.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-09-10 14:06:20 +02:00

332 lines
9.8 KiB
C
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/*
* RTP JPEG-compressed Video Depacketizer, RFC 2435
* Copyright (c) 2012 Samuel Pitoiset
*
* 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 "avformat.h"
#include "rtpdec_formats.h"
#include "libavutil/intreadwrite.h"
#include "libavcodec/mjpeg.h"
/**
* RTP/JPEG specific private data.
*/
struct PayloadContext {
AVIOContext *frame; ///< current frame buffer
uint32_t timestamp; ///< current frame timestamp
int hdr_size; ///< size of the current frame header
};
static PayloadContext *jpeg_new_context(void)
{
return av_mallocz(sizeof(PayloadContext));
}
static inline void free_frame_if_needed(PayloadContext *jpeg)
{
if (jpeg->frame) {
uint8_t *p;
avio_close_dyn_buf(jpeg->frame, &p);
av_free(p);
jpeg->frame = NULL;
}
}
static void jpeg_free_context(PayloadContext *jpeg)
{
free_frame_if_needed(jpeg);
av_free(jpeg);
}
static void jpeg_create_huffman_table(PutBitContext *p, int table_class,
int table_id, const uint8_t *bits_table,
const uint8_t *value_table)
{
int i, n = 0;
put_bits(p, 8, 0);
put_bits(p, 4, table_class);
put_bits(p, 4, table_id);
for (i = 1; i <= 16; i++) {
n += bits_table[i];
put_bits(p, 8, bits_table[i]);
}
for (i = 0; i < n; i++) {
put_bits(p, 8, value_table[i]);
}
}
static int jpeg_create_header(uint8_t *buf, int size, uint32_t type, uint32_t w,
uint32_t h, const uint8_t *qtable, int nb_qtable)
{
PutBitContext pbc;
init_put_bits(&pbc, buf, size);
/* Convert from blocks to pixels. */
w <<= 3;
h <<= 3;
/* SOI */
put_marker(&pbc, SOI);
/* JFIF header */
put_marker(&pbc, APP0);
put_bits(&pbc, 16, 16);
avpriv_put_string(&pbc, "JFIF", 1);
put_bits(&pbc, 16, 0x0201);
put_bits(&pbc, 8, 0);
put_bits(&pbc, 16, 1);
put_bits(&pbc, 16, 1);
put_bits(&pbc, 8, 0);
put_bits(&pbc, 8, 0);
/* DQT */
put_marker(&pbc, DQT);
if (nb_qtable == 2) {
put_bits(&pbc, 16, 2 + 2 * (1 + 64));
} else {
put_bits(&pbc, 16, 2 + 1 * (1 + 64));
}
put_bits(&pbc, 8, 0);
/* Each table is an array of 64 values given in zig-zag
* order, identical to the format used in a JFIF DQT
* marker segment. */
avpriv_copy_bits(&pbc, qtable, 64 * 8);
if (nb_qtable == 2) {
put_bits(&pbc, 8, 1);
avpriv_copy_bits(&pbc, qtable + 64, 64 * 8);
}
/* DHT */
put_marker(&pbc, DHT);
jpeg_create_huffman_table(&pbc, 0, 0, avpriv_mjpeg_bits_dc_luminance,
avpriv_mjpeg_val_dc);
jpeg_create_huffman_table(&pbc, 0, 1, avpriv_mjpeg_bits_dc_chrominance,
avpriv_mjpeg_val_dc);
jpeg_create_huffman_table(&pbc, 1, 0, avpriv_mjpeg_bits_ac_luminance,
avpriv_mjpeg_val_ac_luminance);
jpeg_create_huffman_table(&pbc, 1, 1, avpriv_mjpeg_bits_ac_chrominance,
avpriv_mjpeg_val_ac_chrominance);
/* SOF0 */
put_marker(&pbc, SOF0);
put_bits(&pbc, 16, 17);
put_bits(&pbc, 8, 8);
put_bits(&pbc, 8, h >> 8);
put_bits(&pbc, 8, h);
put_bits(&pbc, 8, w >> 8);
put_bits(&pbc, 8, w);
put_bits(&pbc, 8, 3);
put_bits(&pbc, 8, 1);
put_bits(&pbc, 8, type ? 34 : 33);
put_bits(&pbc, 8, 0);
put_bits(&pbc, 8, 2);
put_bits(&pbc, 8, 17);
put_bits(&pbc, 8, nb_qtable == 2 ? 1 : 0);
put_bits(&pbc, 8, 3);
put_bits(&pbc, 8, 17);
put_bits(&pbc, 8, nb_qtable == 2 ? 1 : 0);
/* SOS */
put_marker(&pbc, SOS);
put_bits(&pbc, 16, 12);
put_bits(&pbc, 8, 3);
put_bits(&pbc, 8, 1);
put_bits(&pbc, 8, 0);
put_bits(&pbc, 8, 2);
put_bits(&pbc, 8, 17);
put_bits(&pbc, 8, 3);
put_bits(&pbc, 8, 17);
put_bits(&pbc, 8, 0);
put_bits(&pbc, 8, 63);
put_bits(&pbc, 8, 0);
/* Fill the buffer. */
flush_put_bits(&pbc);
/* Return the length in bytes of the JPEG header. */
return put_bits_count(&pbc) / 8;
}
static int jpeg_parse_packet(AVFormatContext *ctx, PayloadContext *jpeg,
AVStream *st, AVPacket *pkt, uint32_t *timestamp,
const uint8_t *buf, int len, int flags)
{
uint8_t type, q, width, height;
const uint8_t *qtables = NULL;
uint16_t qtable_len;
uint32_t off;
int ret;
if (len < 8) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/JPEG packet.\n");
return AVERROR_INVALIDDATA;
}
/* Parse the main JPEG header. */
off = AV_RB24(buf + 1); /* fragment byte offset */
type = AV_RB8(buf + 4); /* id of jpeg decoder params */
q = AV_RB8(buf + 5); /* quantization factor (or table id) */
width = AV_RB8(buf + 6); /* frame width in 8 pixel blocks */
height = AV_RB8(buf + 7); /* frame height in 8 pixel blocks */
buf += 8;
len -= 8;
/* Parse the restart marker header. */
if (type > 63) {
av_log(ctx, AV_LOG_ERROR,
"Unimplemented RTP/JPEG restart marker header.\n");
return AVERROR_PATCHWELCOME;
}
/* Parse the quantization table header. */
if (q > 127 && off == 0) {
uint8_t precision;
if (len < 4) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/JPEG packet.\n");
return AVERROR_INVALIDDATA;
}
/* The first byte is reserved for future use. */
precision = AV_RB8(buf + 1); /* size of coefficients */
qtable_len = AV_RB16(buf + 2); /* length in bytes */
buf += 4;
len -= 4;
if (precision)
av_log(ctx, AV_LOG_WARNING, "Only 8-bit precision is supported.\n");
if (q == 255 && qtable_len == 0) {
av_log(ctx, AV_LOG_ERROR,
"Invalid RTP/JPEG packet. Quantization tables not found.\n");
return AVERROR_INVALIDDATA;
}
if (qtable_len > 0) {
if (len < qtable_len) {
av_log(ctx, AV_LOG_ERROR, "Too short RTP/JPEG packet.\n");
return AVERROR_INVALIDDATA;
}
qtables = buf;
buf += qtable_len;
len -= qtable_len;
}
}
if (off == 0) {
/* Start of JPEG data packet. */
uint8_t hdr[1024];
/* Skip the current frame in case of the end packet
* has been lost somewhere. */
free_frame_if_needed(jpeg);
if ((ret = avio_open_dyn_buf(&jpeg->frame)) < 0)
return ret;
jpeg->timestamp = *timestamp;
if (!qtables) {
av_log(ctx, AV_LOG_ERROR,
"Unimplemented default quantization tables.\n");
return AVERROR_PATCHWELCOME;
}
/* Generate a frame and scan headers that can be prepended to the
* RTP/JPEG data payload to produce a JPEG compressed image in
* interchange format. */
jpeg->hdr_size = jpeg_create_header(hdr, sizeof(hdr), type, width,
height, qtables,
qtable_len > 64 ? 2 : 1);
/* Copy JPEG header to frame buffer. */
avio_write(jpeg->frame, hdr, jpeg->hdr_size);
}
if (!jpeg->frame) {
av_log(ctx, AV_LOG_ERROR,
"Received packet without a start chunk; dropping frame.\n");
return AVERROR(EAGAIN);
}
if (jpeg->timestamp != *timestamp) {
/* Skip the current frame if timestamp is incorrect.
* A start packet has been lost somewhere. */
free_frame_if_needed(jpeg);
av_log(ctx, AV_LOG_ERROR, "RTP timestamps don't match.\n");
return AVERROR_INVALIDDATA;
}
if (off != avio_tell(jpeg->frame) - jpeg->hdr_size) {
av_log(ctx, AV_LOG_ERROR,
"Missing packets; dropping frame.\n");
return AVERROR(EAGAIN);
}
/* Copy data to frame buffer. */
avio_write(jpeg->frame, buf, len);
if (flags & RTP_FLAG_MARKER) {
/* End of JPEG data packet. */
PutBitContext pbc;
uint8_t buf[2];
/* Put EOI marker. */
init_put_bits(&pbc, buf, sizeof(buf));
put_marker(&pbc, EOI);
flush_put_bits(&pbc);
avio_write(jpeg->frame, buf, sizeof(buf));
/* Prepare the JPEG packet. */
av_init_packet(pkt);
pkt->size = avio_close_dyn_buf(jpeg->frame, &pkt->data);
if (pkt->size < 0) {
av_log(ctx, AV_LOG_ERROR,
"Error occured when getting frame buffer.\n");
jpeg->frame = NULL;
return pkt->size;
}
pkt->stream_index = st->index;
pkt->destruct = av_destruct_packet;
/* Re-init the frame buffer. */
jpeg->frame = NULL;
return 0;
}
return AVERROR(EAGAIN);
}
RTPDynamicProtocolHandler ff_jpeg_dynamic_handler = {
.enc_name = "JPEG",
.codec_type = AVMEDIA_TYPE_VIDEO,
.codec_id = AV_CODEC_ID_MJPEG,
.alloc = jpeg_new_context,
.free = jpeg_free_context,
.parse_packet = jpeg_parse_packet,
.static_payload_id = 26,
};
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