/*
* MxPEG decoder
* Copyright (c) 2011 Anatoly Nenashev
*
* 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
*/
/**
* @file
* MxPEG decoder
*/
#include "internal.h"
#include "mjpeg.h"
#include "mjpegdec.h"
typedef struct MXpegDecodeContext {
MJpegDecodeContext jpg;
AVFrame picture[2]; /* pictures array */
int picture_index; /* index of current picture */
int got_sof_data; /* true if SOF data successfully parsed */
int got_mxm_bitmask; /* true if MXM bitmask available */
uint8_t *mxm_bitmask; /* bitmask buffer */
unsigned bitmask_size; /* size of bitmask */
int has_complete_frame; /* true if has complete frame */
uint8_t *completion_bitmask; /* completion bitmask of macroblocks */
unsigned mb_width, mb_height; /* size of picture in MB's from MXM header */
} MXpegDecodeContext;
static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
{
MXpegDecodeContext *s = avctx->priv_data;
s->jpg.picture_ptr = &s->picture[0];
return ff_mjpeg_decode_init(avctx);
}
static int mxpeg_decode_app(MXpegDecodeContext *s,
const uint8_t *buf_ptr, int buf_size)
{
int len;
if (buf_size < 2)
return 0;
len = AV_RB16(buf_ptr);
skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
return 0;
}
static int mxpeg_decode_mxm(MXpegDecodeContext *s,
const uint8_t *buf_ptr, int buf_size)
{
unsigned bitmask_size, mb_count;
int i;
s->mb_width = AV_RL16(buf_ptr+4);
s->mb_height = AV_RL16(buf_ptr+6);
mb_count = s->mb_width * s->mb_height;
bitmask_size = (mb_count + 7) >> 3;
if (bitmask_size > buf_size - 12) {
av_log(s->jpg.avctx, AV_LOG_ERROR,
"MXM bitmask is not complete\n");
return AVERROR(EINVAL);
}
if (s->bitmask_size != bitmask_size) {
s->bitmask_size = 0;
av_freep(&s->mxm_bitmask);
s->mxm_bitmask = av_malloc(bitmask_size);
if (!s->mxm_bitmask) {
av_log(s->jpg.avctx, AV_LOG_ERROR,
"MXM bitmask memory allocation error\n");
return AVERROR(ENOMEM);
}
av_freep(&s->completion_bitmask);
s->completion_bitmask = av_mallocz(bitmask_size);
if (!s->completion_bitmask) {
av_log(s->jpg.avctx, AV_LOG_ERROR,
"Completion bitmask memory allocation error\n");
return AVERROR(ENOMEM);
}
s->bitmask_size = bitmask_size;
}
memcpy(s
->mxm_bitmask
, buf_ptr
+ 12, bitmask_size
); s->got_mxm_bitmask = 1;
if (!s->has_complete_frame) {
uint8_t completion_check = 0xFF;
for (i = 0; i < bitmask_size; ++i) {
s->completion_bitmask[i] |= s->mxm_bitmask[i];
completion_check &= s->completion_bitmask[i];
}
s->has_complete_frame = !(completion_check ^ 0xFF);
}
return 0;
}
static int mxpeg_decode_com(MXpegDecodeContext *s,
const uint8_t *buf_ptr, int buf_size)
{
int len, ret = 0;
if (buf_size < 2)
return 0;
len = AV_RB16(buf_ptr);
if (len
> 14 && len
<= buf_size
&& !strncmp(buf_ptr
+ 2, "MXM", 3)) { ret = mxpeg_decode_mxm(s, buf_ptr + 2, len - 2);
}
skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
return ret;
}
static int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg,
AVFrame *reference_ptr)
{
if ((jpg->width + 0x0F)>>4 != s->mb_width ||
(jpg->height + 0x0F)>>4 != s->mb_height) {
av_log(jpg->avctx, AV_LOG_ERROR,
"Picture dimensions stored in SOF and MXM mismatch\n");
return AVERROR(EINVAL);
}
if (reference_ptr->data[0]) {
int i;
for (i = 0; i < MAX_COMPONENTS; ++i) {
if ( (!reference_ptr->data[i] ^ !jpg->picture_ptr->data[i]) ||
reference_ptr->linesize[i] != jpg->picture_ptr->linesize[i]) {
av_log(jpg->avctx, AV_LOG_ERROR,
"Dimensions of current and reference picture mismatch\n");
return AVERROR(EINVAL);
}
}
}
return 0;
}
static int mxpeg_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
MXpegDecodeContext *s = avctx->priv_data;
MJpegDecodeContext *jpg = &s->jpg;
const uint8_t *buf_end, *buf_ptr;
const uint8_t *unescaped_buf_ptr;
int unescaped_buf_size;
int start_code;
int ret;
buf_ptr = buf;
buf_end = buf + buf_size;
jpg->got_picture = 0;
s->got_mxm_bitmask = 0;
while (buf_ptr < buf_end) {
start_code = ff_mjpeg_find_marker(jpg, &buf_ptr, buf_end,
&unescaped_buf_ptr, &unescaped_buf_size);
if (start_code < 0)
goto the_end;
{
init_get_bits(&jpg->gb, unescaped_buf_ptr, unescaped_buf_size*8);
if (start_code >= APP0 && start_code <= APP15) {
mxpeg_decode_app(s, unescaped_buf_ptr, unescaped_buf_size);
}
switch (start_code) {
case SOI:
if (jpg->got_picture) //emulating EOI
goto the_end;
break;
case EOI:
goto the_end;
case DQT:
ret = ff_mjpeg_decode_dqt(jpg);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR,
"quantization table decode error\n");
return ret;
}
break;
case DHT:
ret = ff_mjpeg_decode_dht(jpg);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR,
"huffman table decode error\n");
return ret;
}
break;
case COM:
ret = mxpeg_decode_com(s, unescaped_buf_ptr,
unescaped_buf_size);
if (ret < 0)
return ret;
break;
case SOF0:
s->got_sof_data = 0;
ret = ff_mjpeg_decode_sof(jpg);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR,
"SOF data decode error\n");
return ret;
}
if (jpg->interlaced) {
av_log(avctx, AV_LOG_ERROR,
"Interlaced mode not supported in MxPEG\n");
return AVERROR(EINVAL);
}
s->got_sof_data = 1;
break;
case SOS:
if (!s->got_sof_data) {
av_log(avctx, AV_LOG_WARNING,
"Can not process SOS without SOF data, skipping\n");
break;
}
if (!jpg->got_picture) {
if (jpg->first_picture) {
av_log(avctx, AV_LOG_WARNING,
"First picture has no SOF, skipping\n");
break;
}
if (!s->got_mxm_bitmask){
av_log(avctx, AV_LOG_WARNING,
"Non-key frame has no MXM, skipping\n");
break;
}
/* use stored SOF data to allocate current picture */
av_frame_unref(jpg->picture_ptr);
if ((ret = ff_get_buffer(avctx, jpg->picture_ptr,
AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
jpg->picture_ptr->pict_type = AV_PICTURE_TYPE_P;
jpg->picture_ptr->key_frame = 0;
jpg->got_picture = 1;
} else {
jpg->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
jpg->picture_ptr->key_frame = 1;
}
if (s->got_mxm_bitmask) {
AVFrame *reference_ptr = &s->picture[s->picture_index ^ 1];
if (mxpeg_check_dimensions(s, jpg, reference_ptr) < 0)
break;
/* allocate dummy reference picture if needed */
if (!reference_ptr->data[0] &&
(ret = ff_get_buffer(avctx, reference_ptr,
AV_GET_BUFFER_FLAG_REF)) < 0)
return ret;
ret = ff_mjpeg_decode_sos(jpg, s->mxm_bitmask, reference_ptr);
if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
return ret;
} else {
ret = ff_mjpeg_decode_sos(jpg, NULL, NULL);
if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
return ret;
}
break;
}
buf_ptr += (get_bits_count(&jpg->gb)+7) >> 3;
}
}
the_end:
if (jpg->got_picture) {
int ret = av_frame_ref(data, jpg->picture_ptr);
if (ret < 0)
return ret;
*got_frame = 1;
s->picture_index ^= 1;
jpg->picture_ptr = &s->picture[s->picture_index];
if (!s->has_complete_frame) {
if (!s->got_mxm_bitmask)
s->has_complete_frame = 1;
else
*got_frame = 0;
}
}
return buf_ptr - buf;
}
static av_cold int mxpeg_decode_end(AVCodecContext *avctx)
{
MXpegDecodeContext *s = avctx->priv_data;
MJpegDecodeContext *jpg = &s->jpg;
int i;
jpg->picture_ptr = NULL;
ff_mjpeg_decode_end(avctx);
for (i = 0; i < 2; ++i)
av_frame_unref(&s->picture[i]);
av_freep(&s->mxm_bitmask);
av_freep(&s->completion_bitmask);
return 0;
}
AVCodec ff_mxpeg_decoder = {
.name = "mxpeg",
.long_name = NULL_IF_CONFIG_SMALL("Mobotix MxPEG video"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_MXPEG,
.priv_data_size = sizeof(MXpegDecodeContext),
.init = mxpeg_decode_init,
.close = mxpeg_decode_end,
.decode = mxpeg_decode_frame,
.capabilities = CODEC_CAP_DR1,
.max_lowres = 3,
};