/*
* mpeg-pes interface
*/
#define MAX_STC_DTS_DIFF (INT64_C(90000 * 30)) /* 30 seconds */
static int graphics_processor_decode_pes(PG_DISPLAY_SET **s, PES_BUFFER **p, int64_t stc)
{
if (!s) {
return 0;
}
if (*s == NULL) {
*s = calloc(1, sizeof(PG_DISPLAY_SET));
}
while (*p) {
/* time to decode next segment ? */
if (stc >= 0 && (*p)->dts > stc) {
/* filter out values that seem to be incorrect (if stc is not updated) */
int64_t diff = (*p)->dts - stc;
if (diff < MAX_STC_DTS_DIFF) {
GP_TRACE("Segment dts > stc (%"PRId64" > %"PRId64" ; diff %"PRId64")\n",
(*p)->dts, stc, diff);
return 0;
}
}
/* all fragments present ? */
if (!_join_segment_fragments(*p)) {
GP_TRACE("splitted segment not complete, waiting for next fragment\n");
return 0;
}
if ((*p)->len <= 2) {
BD_DEBUG(DBG_DECODE, "segment too short, skipping (%d bytes)\n", (*p)->len);
pes_buffer_remove(p, *p);
continue;
}
/* decode segment */
GP_TRACE("Decoding segment, dts %010"PRId64" pts %010"PRId64" len %d\n",
(*p)->dts, (*p)->pts, (*p)->len);
(*s)->complete = 0;
_decode_segment(*s, *p);
pes_buffer_remove(p, *p);
if ((*s)->complete) {
return 1;
}
}
return 0;
}
int graphics_processor_decode_pes(PG_DISPLAY_SET **s, PES_BUFFER **p, int64_t stc)
{
if (!s) {
return 0;
}
if (*s == NULL) {
*s = calloc(1, sizeof(PG_DISPLAY_SET));
}
(*s)->complete = 0;
while (*p && !(*s)->complete) {
/* time to decode next segment ? */
if (stc >= 0 && (*p)->dts > stc) {
GP_TRACE("Segment dts > stc (%"PRId64" > %"PRId64" ; diff %"PRId64")\n",
(*p)->dts, stc, (*p)->dts - stc);
return 0;
}
/* all fragments present ? */
if (!_join_segment_fragments(*p)) {
GP_TRACE("splitted segment not complete, waiting for next fragment\n");
return 0;
}
GP_TRACE("Decoding segment, dts %010"PRId64" pts %010"PRId64" len %d\n",
(*p)->dts, (*p)->pts, (*p)->len);
/* decode segment */
if ((*p)->len > 2) {
_decode_segment(*s, *p);
}
pes_buffer_remove(p, *p);
}
return (*s)->complete;
}
/* return 1 if segment is ready for decoding, 0 if more data is needed */
static int _join_segment_fragments(struct pes_buffer_s *p)
{
uint8_t type = p->buf[0];
unsigned id_pos = 0, id_len = 3, sd_pos = 6, data_pos = 0;
if (p->len < 3) {
return 1;
}
/* check segment type */
if (type == PGS_OBJECT) {
id_pos = 3;
sd_pos = 6;
data_pos = 7;
}
else if (type == PGS_IG_COMPOSITION) {
id_pos = 8;
sd_pos = 11;
data_pos = 12;
}
else {
return 1;
}
/* check sequence descriptor - is segment complete ? */
BD_PG_SEQUENCE_DESCRIPTOR sd;
BITBUFFER bb;
bb_init(&bb, p->buf + sd_pos, 3);
pg_decode_sequence_descriptor(&bb, &sd);
if (sd.last_in_seq) {
return 1;
}
if (!sd.first_in_seq) {
return 1;
}
/* find next fragment(s) */
PES_BUFFER *next;
while (NULL != (next = _find_segment_by_idv(p->next, p->buf[0], id_pos, p->buf + id_pos, id_len))) {
bb_init(&bb, next->buf + sd_pos, 3);
pg_decode_sequence_descriptor(&bb, &sd);
_join_fragments(p, next, data_pos);
pes_buffer_remove(&p, next);
if (sd.last_in_seq) {
/* set first + last in sequence descriptor */
p->buf[sd_pos] = 0xff;
return 1;
}
}
/* do not delay decoding if there are other segments queued (missing fragment ?) */
return !!p->next;
}
