void CMPEG2HeaderParser::ParseMPEG2Header(const BYTE *pData, size_t length)
{
if (length < 16)
return;
GetBitContext gb;
const uint8_t *start = pData;
const uint8_t *end = start + length;
const uint8_t *next = nullptr;
int size;
start = find_next_marker(start, end);
next = start;
for(; next < end; start = next) {
next = find_next_marker(start + 4, end);
size = (int)(next - start - 4);
if(size <= 0) continue;
init_get_bits(&gb, start + 4, (size - 4) * 8);
switch(AV_RB32(start)) {
case SEQ_START_CODE:
MPEG2ParseSequenceHeader(&gb);
break;
case EXT_START_CODE:
MPEG2ParseExtHeader(&gb);
break;
}
}
}
static void vc1_extract_headers(AVCodecParserContext *s, AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
VC1ParseContext *vpc = (VC1ParseContext *)s->priv_data;
GetBitContext gb;
const uint8_t *start, *end, *next;
uint8_t *buf2 = (uint8_t *)av_mallocz(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
vpc->v.s.avctx = avctx;
vpc->v.parse_only = 1;
next = buf;
s->repeat_pict = 0;
for(start = buf, end = buf + buf_size; next < end; start = next){
int buf2_size, size;
next = find_next_marker(start + 4, end);
size = next - start - 4;
buf2_size = vc1_unescape_buffer(start + 4, size, buf2);
init_get_bits(&gb, buf2, buf2_size * 8);
if(size <= 0) continue;
switch(AV_RB32(start)){
case VC1_CODE_SEQHDR:
vc1_decode_sequence_header(avctx, &vpc->v, &gb);
break;
case VC1_CODE_ENTRYPOINT:
vc1_decode_entry_point(avctx, &vpc->v, &gb);
break;
case VC1_CODE_FRAME:
if(vpc->v.profile < PROFILE_ADVANCED)
vc1_parse_frame_header (&vpc->v, &gb);
else
vc1_parse_frame_header_adv(&vpc->v, &gb);
/* keep AV_PICTURE_TYPE_BI internal to VC1 */
if (vpc->v.s.pict_type == AV_PICTURE_TYPE_BI)
s->pict_type = AV_PICTURE_TYPE_B;
else
s->pict_type = vpc->v.s.pict_type;
if (avctx->ticks_per_frame > 1){
// process pulldown flags
s->repeat_pict = 1;
// Pulldown flags are only valid when 'broadcast' has been set.
// So ticks_per_frame will be 2
if (vpc->v.rff){
// repeat field
s->repeat_pict = 2;
}else if (vpc->v.rptfrm){
// repeat frames
s->repeat_pict = vpc->v.rptfrm * 2 + 1;
}
}
break;
}
}
av_free(buf2);
}
void CVC1HeaderParser::ParseVC1Header(const BYTE *pData, size_t length, AVCodecID codec)
{
GetBitContext gb;
if (codec == AV_CODEC_ID_VC1) {
if (length < 16)
return;
const uint8_t *start = pData;
const uint8_t *end = start + length;
const uint8_t *next = nullptr;
int size, buf2_size;
uint8_t *buf2;
buf2 = (uint8_t *)av_mallocz(length + FF_INPUT_BUFFER_PADDING_SIZE);
start = find_next_marker(start, end);
next = start;
for(; next < end; start = next) {
next = find_next_marker(start + 4, end);
size = (int)(next - start - 4);
if(size <= 0) continue;
buf2_size = vc1_unescape_buffer(start + 4, size, buf2);
init_get_bits(&gb, buf2, buf2_size * 8);
switch(AV_RB32(start)) {
case VC1_CODE_SEQHDR:
VC1ParseSequenceHeader(&gb);
break;
}
}
av_freep(&buf2);
} else if (codec == AV_CODEC_ID_WMV3) {
if (length < 4)
return;
init_get_bits(&gb, pData, length * 8);
VC1ParseSequenceHeader(&gb);
}
}
static void vc1_extract_headers(AVCodecParserContext *s, AVCodecContext *avctx,
const uint8_t *buf, int buf_size)
{
VC1ParseContext *vpc = s->priv_data;
GetBitContext gb;
const uint8_t *start, *end, *next;
uint8_t *buf2 = av_mallocz(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
vpc->v.s.avctx = avctx;
vpc->v.parse_only = 1;
next = buf;
for(start = buf, end = buf + buf_size; next < end; start = next)
{
int buf2_size, size;
next = find_next_marker(start + 4, end);
size = next - start - 4;
buf2_size = vc1_unescape_buffer(start + 4, size, buf2);
init_get_bits(&gb, buf2, buf2_size * 8);
if(size <= 0) continue;
switch(AV_RB32(start))
{
case VC1_CODE_SEQHDR:
vc1_decode_sequence_header(avctx, &vpc->v, &gb);
break;
case VC1_CODE_ENTRYPOINT:
vc1_decode_entry_point(avctx, &vpc->v, &gb);
break;
case VC1_CODE_FRAME:
if(vpc->v.profile < PROFILE_ADVANCED)
vc1_parse_frame_header (&vpc->v, &gb);
else
vc1_parse_frame_header_adv(&vpc->v, &gb);
/* keep FF_BI_TYPE internal to VC1 */
if (vpc->v.s.pict_type == FF_BI_TYPE)
s->pict_type = FF_B_TYPE;
else
s->pict_type = vpc->v.s.pict_type;
break;
}
}
av_free(buf2);
}
static AVPictureType parse_picture_type(const uint8_t *buf, int buflen, CVC1HeaderParser *vc1Header)
{
AVPictureType pictype = AV_PICTURE_TYPE_NONE;
int skipped = 0;
const BYTE *framestart = buf;
if (IS_MARKER(AV_RB32(buf))) {
framestart = NULL;
const BYTE *start, *end, *next;
next = buf;
for (start = buf, end = buf + buflen; next < end; start = next) {
if (AV_RB32(start) == VC1_CODE_FRAME) {
framestart = start + 4;
break;
}
next = find_next_marker(start + 4, end);
}
}
if (framestart) {
GetBitContext gb;
init_get_bits(&gb, framestart, (buflen - (framestart-buf))*8);
if (vc1Header->hdr.profile == PROFILE_ADVANCED) {
int fcm = PROGRESSIVE;
if (vc1Header->hdr.interlaced)
fcm = decode012(&gb);
if (fcm == ILACE_FIELD) {
int fptype = get_bits(&gb, 3);
pictype = (fptype & 2) ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
if (fptype & 4) // B-picture
pictype = (fptype & 2) ? AV_PICTURE_TYPE_BI : AV_PICTURE_TYPE_B;
} else {
switch (get_unary(&gb, 0, 4)) {
case 0:
pictype = AV_PICTURE_TYPE_P;
break;
case 1:
pictype = AV_PICTURE_TYPE_B;
break;
case 2:
pictype = AV_PICTURE_TYPE_I;
break;
case 3:
pictype = AV_PICTURE_TYPE_BI;
break;
case 4:
pictype = AV_PICTURE_TYPE_P; // skipped pic
skipped = 1;
break;
}
}
} else {
if (vc1Header->hdr.finterp)
skip_bits1(&gb);
skip_bits(&gb, 2); // framecnt
if (vc1Header->hdr.rangered)
skip_bits1(&gb);
int pic = get_bits1(&gb);
if (vc1Header->hdr.bframes) {
if (!pic) {
if (get_bits1(&gb)) {
pictype = AV_PICTURE_TYPE_I;
} else {
pictype = AV_PICTURE_TYPE_B;
}
} else {
pictype = AV_PICTURE_TYPE_P;
}
} else {
pictype = pic ? AV_PICTURE_TYPE_P : AV_PICTURE_TYPE_I;
}
}
}
return pictype;
}
int av_vc1_decode_frame(AVCodecContext *avctx, const uint8_t *buf, int buf_size, int *nFrameSize)
{
int n_slices = 0, i;
VC1Context *v = avctx->priv_data;
MpegEncContext *s = &v->s;
uint8_t *buf2 = NULL;
const uint8_t *buf_start = buf, *buf_start_second_field = NULL;
struct {
uint8_t *buf;
GetBitContext gb;
int mby_start;
} *slices = NULL, *tmp;
v->second_field = 0;
*nFrameSize = 0;
/* for advanced profile we may need to parse and unescape data */
if (avctx->codec_id == AV_CODEC_ID_VC1 || avctx->codec_id == AV_CODEC_ID_VC1IMAGE) {
int buf_size2 = 0;
buf2 = av_mallocz(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (IS_MARKER(AV_RB32(buf))) { /* frame starts with marker and needs to be parsed */
const uint8_t *start, *end, *next;
int size;
next = buf;
for (start = buf, end = buf + buf_size; next < end; start = next) {
next = find_next_marker(start + 4, end);
size = next - start - 4;
if (size <= 0) continue;
switch (AV_RB32(start)) {
case VC1_CODE_FRAME:
buf_start = start;
buf_size2 = vc1_unescape_buffer(start + 4, size, buf2);
break;
case VC1_CODE_FIELD: {
int buf_size3;
buf_start_second_field = start;
slices = av_realloc(slices, sizeof(*slices) * (n_slices + 1));
if (!slices)
goto err;
slices[n_slices].buf = av_mallocz(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!slices[n_slices].buf)
goto err;
buf_size3 = vc1_unescape_buffer(start + 4, size,
slices[n_slices].buf);
init_get_bits(&slices[n_slices].gb, slices[n_slices].buf,
buf_size3 << 3);
/* assuming that the field marker is at the exact middle,
hope it's correct */
slices[n_slices].mby_start = s->mb_height >> 1;
n_slices++;
break;
}
case VC1_CODE_ENTRYPOINT: /* it should be before frame data */
buf_size2 = vc1_unescape_buffer(start + 4, size, buf2);
init_get_bits(&s->gb, buf2, buf_size2 * 8);
ff_vc1_decode_entry_point(avctx, v, &s->gb);
break;
case VC1_CODE_SLICE: {
int buf_size3;
slices = av_realloc(slices, sizeof(*slices) * (n_slices + 1));
if (!slices)
goto err;
slices[n_slices].buf = av_mallocz(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!slices[n_slices].buf)
goto err;
buf_size3 = vc1_unescape_buffer(start + 4, size,
slices[n_slices].buf);
init_get_bits(&slices[n_slices].gb, slices[n_slices].buf,
buf_size3 << 3);
slices[n_slices].mby_start = get_bits(&slices[n_slices].gb, 9);
n_slices++;
break;
}
}
}
} else if (v->interlace && ((buf[0] & 0xC0) == 0xC0)) { /* WVC1 interlaced stores both fields divided by marker */
goto err;
buf_size3 = vc1_unescape_buffer(start + 4, size,
slices[n_slices].buf);
init_get_bits(&slices[n_slices].gb, slices[n_slices].buf,
buf_size3 << 3);
slices[n_slices].mby_start = get_bits(&slices[n_slices].gb, 9);
n_slices++;
break;
}
}
}
} else if (v->interlace && ((buf[0] & 0xC0) == 0xC0)) { /* WVC1 interlaced stores both fields divided by marker */
const uint8_t *divider;
int buf_size3;
divider = find_next_marker(buf, buf + buf_size);
if ((divider == (buf + buf_size)) || AV_RB32(divider) != VC1_CODE_FIELD) {
av_log(avctx, AV_LOG_ERROR, "Error in WVC1 interlaced frame\n");
goto err;
} else { /* found field marker, unescape second field */
buf_start_second_field = divider;
tmp = av_realloc(slices, sizeof(*slices) * (n_slices + 1));
if (!tmp)
goto err;
slices = tmp;
slices[n_slices].buf = av_mallocz(buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!slices[n_slices].buf)
goto err;
buf_size3 = vc1_unescape_buffer(divider + 4, buf + buf_size - divider - 4, slices[n_slices].buf);
init_get_bits(&slices[n_slices].gb, slices[n_slices].buf,
buf_size3 << 3);
