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-rw-r--r--libmpeg2/header.c224
1 files changed, 147 insertions, 77 deletions
diff --git a/libmpeg2/header.c b/libmpeg2/header.c
index ae8b228a63..040651d20e 100644
--- a/libmpeg2/header.c
+++ b/libmpeg2/header.c
@@ -246,7 +246,7 @@ static int sequence_ext (mpeg2dec_t * mpeg2dec)
sequence->vbv_buffer_size |= buffer[4] << 21;
sequence->frame_period =
- sequence->frame_period * ((buffer[5]&31)+1) / (((buffer[5]>>2)&3)+1);
+ sequence->frame_period * ((buffer[5]&31)+1) / (((buffer[5]>>5)&3)+1);
mpeg2dec->ext_state = SEQ_DISPLAY_EXT;
@@ -257,12 +257,11 @@ static int sequence_display_ext (mpeg2dec_t * mpeg2dec)
{
uint8_t * buffer = mpeg2dec->chunk_start;
mpeg2_sequence_t * sequence = &(mpeg2dec->new_sequence);
- uint32_t flags;
- flags = ((sequence->flags & ~SEQ_MASK_VIDEO_FORMAT) |
- ((buffer[0]<<4) & SEQ_MASK_VIDEO_FORMAT));
+ sequence->flags = ((sequence->flags & ~SEQ_MASK_VIDEO_FORMAT) |
+ ((buffer[0]<<4) & SEQ_MASK_VIDEO_FORMAT));
if (buffer[0] & 1) {
- flags |= SEQ_FLAG_COLOUR_DESCRIPTION;
+ sequence->flags |= SEQ_FLAG_COLOUR_DESCRIPTION;
sequence->colour_primaries = buffer[1];
sequence->transfer_characteristics = buffer[2];
sequence->matrix_coefficients = buffer[3];
@@ -281,6 +280,17 @@ static int sequence_display_ext (mpeg2dec_t * mpeg2dec)
return 0;
}
+static inline void simplify (unsigned int * u, unsigned int * v)
+{
+ unsigned int a, b, tmp;
+
+ a = *u; b = *v;
+ while (a) { /* find greatest common divisor */
+ tmp = a; a = b % tmp; b = tmp;
+ }
+ *u /= b; *v /= b;
+}
+
static inline void finalize_sequence (mpeg2_sequence_t * sequence)
{
int width;
@@ -317,8 +327,10 @@ static inline void finalize_sequence (mpeg2_sequence_t * sequence)
sequence->pixel_width = 64; sequence->pixel_height = 45; return;
case 6: /* 720x480 16:9 */
sequence->pixel_width = 32; sequence->pixel_height = 27; return;
- case 12: /* 720*480 4:3 */
- sequence->pixel_width = 8; sequence->pixel_height = 9; return;
+ case 8: /* BT.601 625 lines 4:3 */
+ sequence->pixel_width = 59; sequence->pixel_height = 54; return;
+ case 12: /* BT.601 525 lines 4:3 */
+ sequence->pixel_width = 10; sequence->pixel_height = 11; return;
default:
height = 88 * sequence->pixel_width + 1171;
width = 2000;
@@ -327,22 +339,89 @@ static inline void finalize_sequence (mpeg2_sequence_t * sequence)
sequence->pixel_width = width;
sequence->pixel_height = height;
- while (width) { /* find greatest common divisor */
- int tmp = width;
- width = height % tmp;
- height = tmp;
+ simplify (&sequence->pixel_width, &sequence->pixel_height);
+}
+
+int mpeg2_guess_aspect (const mpeg2_sequence_t * sequence,
+ unsigned int * pixel_width,
+ unsigned int * pixel_height)
+{
+ static struct {
+ unsigned int width, height;
+ } video_modes[] = {
+ {720, 576}, /* 625 lines, 13.5 MHz (D1, DV, DVB, DVD) */
+ {704, 576}, /* 625 lines, 13.5 MHz (1/1 D1, DVB, DVD, 4CIF) */
+ {544, 576}, /* 625 lines, 10.125 MHz (DVB, laserdisc) */
+ {528, 576}, /* 625 lines, 10.125 MHz (3/4 D1, DVB, laserdisc) */
+ {480, 576}, /* 625 lines, 9 MHz (2/3 D1, DVB, SVCD) */
+ {352, 576}, /* 625 lines, 6.75 MHz (D2, 1/2 D1, CVD, DVB, DVD) */
+ {352, 288}, /* 625 lines, 6.75 MHz, 1 field (D4, VCD, DVB, DVD, CIF) */
+ {176, 144}, /* 625 lines, 3.375 MHz, half field (QCIF) */
+ {720, 486}, /* 525 lines, 13.5 MHz (D1) */
+ {704, 486}, /* 525 lines, 13.5 MHz */
+ {720, 480}, /* 525 lines, 13.5 MHz (DV, DSS, DVD) */
+ {704, 480}, /* 525 lines, 13.5 MHz (1/1 D1, ATSC, DVD) */
+ {544, 480}, /* 525 lines. 10.125 MHz (DSS, laserdisc) */
+ {528, 480}, /* 525 lines. 10.125 MHz (3/4 D1, laserdisc) */
+ {480, 480}, /* 525 lines, 9 MHz (2/3 D1, SVCD) */
+ {352, 480}, /* 525 lines, 6.75 MHz (D2, 1/2 D1, CVD, DVD) */
+ {352, 240} /* 525 lines. 6.75 MHz, 1 field (D4, VCD, DSS, DVD) */
+ };
+ unsigned int width, height, pix_width, pix_height, i, DAR_16_9;
+
+ *pixel_width = sequence->pixel_width;
+ *pixel_height = sequence->pixel_height;
+ width = sequence->picture_width;
+ height = sequence->picture_height;
+ for (i = 0; i < sizeof (video_modes) / sizeof (video_modes[0]); i++)
+ if (width == video_modes[i].width && height == video_modes[i].height)
+ break;
+ if (i == sizeof (video_modes) / sizeof (video_modes[0]) ||
+ (sequence->pixel_width == 1 && sequence->pixel_height == 1) ||
+ width != sequence->display_width || height != sequence->display_height)
+ return 0;
+
+ for (pix_height = 1; height * pix_height < 480; pix_height <<= 1);
+ height *= pix_height;
+ for (pix_width = 1; width * pix_width <= 352; pix_width <<= 1);
+ width *= pix_width;
+
+ if (! (sequence->flags & SEQ_FLAG_MPEG2)) {
+ static unsigned int mpeg1_check[2][2] = {{11, 54}, {27, 45}};
+ DAR_16_9 = (sequence->pixel_height == 27 ||
+ sequence->pixel_height == 45);
+ if (width < 704 ||
+ sequence->pixel_height != mpeg1_check[DAR_16_9][height == 576])
+ return 0;
+ } else {
+ DAR_16_9 = (3 * sequence->picture_width * sequence->pixel_width >
+ 4 * sequence->picture_height * sequence->pixel_height);
+ switch (width) {
+ case 528: case 544: pix_width *= 4; pix_height *= 3; break;
+ case 480: pix_width *= 3; pix_height *= 2; break;
+ }
+ }
+ if (DAR_16_9) {
+ pix_width *= 4; pix_height *= 3;
+ }
+ if (height == 576) {
+ pix_width *= 59; pix_height *= 54;
+ } else {
+ pix_width *= 10; pix_height *= 11;
}
- sequence->pixel_width /= height;
- sequence->pixel_height /= height;
+ *pixel_width = pix_width;
+ *pixel_height = pix_height;
+ simplify (pixel_width, pixel_height);
+ return (height == 576) ? 1 : 2;
}
-static void copy_matrix (mpeg2dec_t * mpeg2dec, int index)
+static void copy_matrix (mpeg2dec_t * mpeg2dec, int idx)
{
- if (memcmp (mpeg2dec->quantizer_matrix[index],
- mpeg2dec->new_quantizer_matrix[index], 64)) {
- memcpy (mpeg2dec->quantizer_matrix[index],
- mpeg2dec->new_quantizer_matrix[index], 64);
- mpeg2dec->scaled[index] = -1;
+ if (memcmp (mpeg2dec->quantizer_matrix[idx],
+ mpeg2dec->new_quantizer_matrix[idx], 64)) {
+ memcpy (mpeg2dec->quantizer_matrix[idx],
+ mpeg2dec->new_quantizer_matrix[idx], 64);
+ mpeg2dec->scaled[idx] = -1;
}
}
@@ -392,31 +471,30 @@ void mpeg2_header_sequence_finalize (mpeg2dec_t * mpeg2dec)
(sequence->chroma_height == sequence->height));
if (mpeg2dec->sequence.width != (unsigned)-1) {
- unsigned int new_byte_rate;
-
/*
* According to 6.1.1.6, repeat sequence headers should be
- * identical to the original. However some DVDs dont respect
- * that and have different bitrates in the repeat sequence
- * headers. So we'll ignore that in the comparison and still
- * consider these as repeat sequence headers.
- *
- * However, be careful not to alter the current sequence when
- * returning STATE_INVALID_END.
+ * identical to the original. However some encoders do not
+ * respect that and change various fields (including bitrate
+ * and aspect ratio) in the repeat sequence headers. So we
+ * choose to be as conservative as possible and only restart
+ * the decoder if the width, height, chroma_width,
+ * chroma_height or low_delay flag are modified.
*/
- new_byte_rate = sequence->byte_rate;
- sequence->byte_rate = mpeg2dec->sequence.byte_rate;
- if (memcmp (&(mpeg2dec->sequence), sequence,
- sizeof (mpeg2_sequence_t))) {
+ if (sequence->width != mpeg2dec->sequence.width ||
+ sequence->height != mpeg2dec->sequence.height ||
+ sequence->chroma_width != mpeg2dec->sequence.chroma_width ||
+ sequence->chroma_height != mpeg2dec->sequence.chroma_height ||
+ ((sequence->flags ^ mpeg2dec->sequence.flags) &
+ SEQ_FLAG_LOW_DELAY)) {
decoder->stride_frame = sequence->width;
- sequence->byte_rate = new_byte_rate;
mpeg2_header_end (mpeg2dec);
mpeg2dec->action = invalid_end_action;
mpeg2dec->state = STATE_INVALID_END;
return;
}
- sequence->byte_rate = new_byte_rate;
- mpeg2dec->state = STATE_SEQUENCE_REPEATED;
+ mpeg2dec->state = (memcmp (&(mpeg2dec->sequence), sequence,
+ sizeof (mpeg2_sequence_t)) ?
+ STATE_SEQUENCE_MODIFIED : STATE_SEQUENCE_REPEATED);
} else
decoder->stride_frame = sequence->width;
mpeg2dec->sequence = *sequence;
@@ -468,62 +546,53 @@ void mpeg2_set_fbuf (mpeg2dec_t * mpeg2dec, int b_type)
}
}
-mpeg2_state_t mpeg2_header_picture_start (mpeg2dec_t * mpeg2dec)
+int mpeg2_header_picture (mpeg2dec_t * mpeg2dec)
{
+ uint8_t * buffer = mpeg2dec->chunk_start;
mpeg2_picture_t * picture = &(mpeg2dec->new_picture);
+ mpeg2_decoder_t * decoder = &(mpeg2dec->decoder);
+ int type;
mpeg2dec->state = ((mpeg2dec->state != STATE_SLICE_1ST) ?
STATE_PICTURE : STATE_PICTURE_2ND);
- picture->flags = 0;
+ mpeg2dec->ext_state = PIC_CODING_EXT;
+
+ picture->temporal_reference = (buffer[0] << 2) | (buffer[1] >> 6);
+
+ type = (buffer [1] >> 3) & 7;
+ if (type == PIC_FLAG_CODING_TYPE_P || type == PIC_FLAG_CODING_TYPE_B) {
+ /* forward_f_code and backward_f_code - used in mpeg1 only */
+ decoder->f_motion.f_code[1] = (buffer[3] >> 2) & 1;
+ decoder->f_motion.f_code[0] =
+ (((buffer[3] << 1) | (buffer[4] >> 7)) & 7) - 1;
+ decoder->b_motion.f_code[1] = (buffer[4] >> 6) & 1;
+ decoder->b_motion.f_code[0] = ((buffer[4] >> 3) & 7) - 1;
+ }
+
+ picture->flags = PIC_FLAG_PROGRESSIVE_FRAME | type;
picture->tag = picture->tag2 = 0;
if (mpeg2dec->num_tags) {
- if (mpeg2dec->bytes_since_tag >= 4) {
+ if (mpeg2dec->bytes_since_tag >= mpeg2dec->chunk_ptr - buffer + 4) {
mpeg2dec->num_tags = 0;
picture->tag = mpeg2dec->tag_current;
picture->tag2 = mpeg2dec->tag2_current;
- picture->flags = PIC_FLAG_TAGS;
+ picture->flags |= PIC_FLAG_TAGS;
} else if (mpeg2dec->num_tags > 1) {
mpeg2dec->num_tags = 1;
picture->tag = mpeg2dec->tag_previous;
picture->tag2 = mpeg2dec->tag2_previous;
- picture->flags = PIC_FLAG_TAGS;
+ picture->flags |= PIC_FLAG_TAGS;
}
}
+ picture->nb_fields = 2;
picture->display_offset[0].x = picture->display_offset[1].x =
picture->display_offset[2].x = mpeg2dec->display_offset_x;
picture->display_offset[0].y = picture->display_offset[1].y =
picture->display_offset[2].y = mpeg2dec->display_offset_y;
- return mpeg2_parse_header (mpeg2dec);
-}
-
-int mpeg2_header_picture (mpeg2dec_t * mpeg2dec)
-{
- uint8_t * buffer = mpeg2dec->chunk_start;
- mpeg2_picture_t * picture = &(mpeg2dec->new_picture);
- mpeg2_decoder_t * decoder = &(mpeg2dec->decoder);
- int type;
-
- type = (buffer [1] >> 3) & 7;
- mpeg2dec->ext_state = PIC_CODING_EXT;
-
- picture->temporal_reference = (buffer[0] << 2) | (buffer[1] >> 6);
-
- picture->flags |= type;
-
- if (type == PIC_FLAG_CODING_TYPE_P || type == PIC_FLAG_CODING_TYPE_B) {
- /* forward_f_code and backward_f_code - used in mpeg1 only */
- decoder->f_motion.f_code[1] = (buffer[3] >> 2) & 1;
- decoder->f_motion.f_code[0] =
- (((buffer[3] << 1) | (buffer[4] >> 7)) & 7) - 1;
- decoder->b_motion.f_code[1] = (buffer[4] >> 6) & 1;
- decoder->b_motion.f_code[0] = ((buffer[4] >> 3) & 7) - 1;
- }
/* XXXXXX decode extra_information_picture as well */
- picture->nb_fields = 2;
-
- mpeg2dec->q_scale_type = 0;
+ decoder->q_scale_type = 0;
decoder->intra_dc_precision = 7;
decoder->frame_pred_frame_dct = 1;
decoder->concealment_motion_vectors = 0;
@@ -570,10 +639,11 @@ static int picture_coding_ext (mpeg2dec_t * mpeg2dec)
decoder->top_field_first = buffer[3] >> 7;
decoder->frame_pred_frame_dct = (buffer[3] >> 6) & 1;
decoder->concealment_motion_vectors = (buffer[3] >> 5) & 1;
- mpeg2dec->q_scale_type = buffer[3] & 16;
+ decoder->q_scale_type = buffer[3] & 16;
decoder->intra_vlc_format = (buffer[3] >> 3) & 1;
decoder->scan = (buffer[3] & 4) ? mpeg2_scan_alt : mpeg2_scan_norm;
- flags |= (buffer[4] & 0x80) ? PIC_FLAG_PROGRESSIVE_FRAME : 0;
+ if (!(buffer[4] & 0x80))
+ flags &= ~PIC_FLAG_PROGRESSIVE_FRAME;
if (buffer[4] & 0x40)
flags |= (((buffer[4]<<26) | (buffer[5]<<18) | (buffer[6]<<10)) &
PIC_MASK_COMPOSITE_DISPLAY) | PIC_FLAG_COMPOSITE_DISPLAY;
@@ -794,7 +864,7 @@ int mpeg2_header_user_data (mpeg2dec_t * mpeg2dec)
return 0;
}
-static void prescale (mpeg2dec_t * mpeg2dec, int index)
+static void prescale (mpeg2dec_t * mpeg2dec, int idx)
{
static int non_linear_scale [] = {
0, 1, 2, 3, 4, 5, 6, 7,
@@ -805,14 +875,14 @@ static void prescale (mpeg2dec_t * mpeg2dec, int index)
int i, j, k;
mpeg2_decoder_t * decoder = &(mpeg2dec->decoder);
- if (mpeg2dec->scaled[index] != mpeg2dec->q_scale_type) {
- mpeg2dec->scaled[index] = mpeg2dec->q_scale_type;
+ if (mpeg2dec->scaled[idx] != decoder->q_scale_type) {
+ mpeg2dec->scaled[idx] = decoder->q_scale_type;
for (i = 0; i < 32; i++) {
- k = mpeg2dec->q_scale_type ? non_linear_scale[i] : (i << 1);
+ k = decoder->q_scale_type ? non_linear_scale[i] : (i << 1);
decoder->quantizer_scales[i] = k;
for (j = 0; j < 64; j++)
- decoder->quantizer_prescale[index][i][j] =
- k * mpeg2dec->quantizer_matrix[index][j];
+ decoder->quantizer_prescale[idx][i][j] =
+ k * mpeg2dec->quantizer_matrix[idx][j];
}
}
}
@@ -864,7 +934,7 @@ mpeg2_state_t mpeg2_header_slice_start (mpeg2dec_t * mpeg2dec)
mpeg2dec->fbuf[b_type]->buf);
}
mpeg2dec->action = NULL;
- return (mpeg2_state_t)-1;
+ return STATE_INTERNAL_NORETURN;
}
static mpeg2_state_t seek_sequence (mpeg2dec_t * mpeg2dec)
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-26 07:55:34 +0000