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FFmpeg/libavcodec/cbs_mpeg2_syntax_template.c
Andreas Rheinhardt 0e66e1b61e cbs_mpeg2: Decompose Sequence End
Sequence End units (or actually, sequence_end_codes) have up until now
not been decomposed; in fact due to a bug in cbs_mpeg2_split_fragment they
have mostly been treated as part of the preceding unit. So implement
decomposing them as preparation for fixing said bug.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
2019-07-29 22:25:10 +01:00

426 lines
12 KiB
C

/*
* 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
*/
static int FUNC(sequence_header)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawSequenceHeader *current)
{
CodedBitstreamMPEG2Context *mpeg2 = ctx->priv_data;
int err, i;
HEADER("Sequence Header");
ui(8, sequence_header_code);
uir(12, horizontal_size_value);
uir(12, vertical_size_value);
mpeg2->horizontal_size = current->horizontal_size_value;
mpeg2->vertical_size = current->vertical_size_value;
uir(4, aspect_ratio_information);
uir(4, frame_rate_code);
ui(18, bit_rate_value);
marker_bit();
ui(10, vbv_buffer_size_value);
ui(1, constrained_parameters_flag);
ui(1, load_intra_quantiser_matrix);
if (current->load_intra_quantiser_matrix) {
for (i = 0; i < 64; i++)
uirs(8, intra_quantiser_matrix[i], 1, i);
}
ui(1, load_non_intra_quantiser_matrix);
if (current->load_non_intra_quantiser_matrix) {
for (i = 0; i < 64; i++)
uirs(8, non_intra_quantiser_matrix[i], 1, i);
}
return 0;
}
static int FUNC(user_data)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawUserData *current)
{
size_t k;
int err;
HEADER("User Data");
ui(8, user_data_start_code);
#ifdef READ
k = get_bits_left(rw);
av_assert0(k % 8 == 0);
current->user_data_length = k /= 8;
if (k > 0) {
current->user_data_ref = av_buffer_allocz(k + AV_INPUT_BUFFER_PADDING_SIZE);
if (!current->user_data_ref)
return AVERROR(ENOMEM);
current->user_data = current->user_data_ref->data;
}
#endif
for (k = 0; k < current->user_data_length; k++)
uis(8, user_data[k], 1, k);
return 0;
}
static int FUNC(sequence_extension)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawSequenceExtension *current)
{
CodedBitstreamMPEG2Context *mpeg2 = ctx->priv_data;
int err;
HEADER("Sequence Extension");
ui(8, profile_and_level_indication);
ui(1, progressive_sequence);
ui(2, chroma_format);
ui(2, horizontal_size_extension);
ui(2, vertical_size_extension);
mpeg2->horizontal_size = (mpeg2->horizontal_size & 0xfff) |
current->horizontal_size_extension << 12;
mpeg2->vertical_size = (mpeg2->vertical_size & 0xfff) |
current->vertical_size_extension << 12;
mpeg2->progressive_sequence = current->progressive_sequence;
ui(12, bit_rate_extension);
marker_bit();
ui(8, vbv_buffer_size_extension);
ui(1, low_delay);
ui(2, frame_rate_extension_n);
ui(5, frame_rate_extension_d);
return 0;
}
static int FUNC(sequence_display_extension)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawSequenceDisplayExtension *current)
{
int err;
HEADER("Sequence Display Extension");
ui(3, video_format);
ui(1, colour_description);
if (current->colour_description) {
#ifdef READ
#define READ_AND_PATCH(name) do { \
ui(8, name); \
if (current->name == 0) { \
current->name = 2; \
av_log(ctx->log_ctx, AV_LOG_WARNING, "%s in a sequence display " \
"extension had the invalid value 0. Setting it to 2 " \
"(meaning unknown) instead.\n", #name); \
} \
} while (0)
READ_AND_PATCH(colour_primaries);
READ_AND_PATCH(transfer_characteristics);
READ_AND_PATCH(matrix_coefficients);
#undef READ_AND_PATCH
#else
uir(8, colour_primaries);
uir(8, transfer_characteristics);
uir(8, matrix_coefficients);
#endif
} else {
infer(colour_primaries, 2);
infer(transfer_characteristics, 2);
infer(matrix_coefficients, 2);
}
ui(14, display_horizontal_size);
marker_bit();
ui(14, display_vertical_size);
return 0;
}
static int FUNC(group_of_pictures_header)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawGroupOfPicturesHeader *current)
{
int err;
HEADER("Group of Pictures Header");
ui(8, group_start_code);
ui(25, time_code);
ui(1, closed_gop);
ui(1, broken_link);
return 0;
}
static int FUNC(extra_information)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawExtraInformation *current,
const char *element_name, const char *marker_name)
{
int err;
size_t k;
#ifdef READ
GetBitContext start = *rw;
uint8_t bit;
for (k = 0; nextbits(1, 1, bit); k++)
skip_bits(rw, 1 + 8);
current->extra_information_length = k;
if (k > 0) {
*rw = start;
current->extra_information_ref =
av_buffer_allocz(k + AV_INPUT_BUFFER_PADDING_SIZE);
if (!current->extra_information_ref)
return AVERROR(ENOMEM);
current->extra_information = current->extra_information_ref->data;
}
#endif
for (k = 0; k < current->extra_information_length; k++) {
bit(marker_name, 1);
xuia(8, element_name,
current->extra_information[k], 0, 255, 1, k);
}
bit(marker_name, 0);
return 0;
}
static int FUNC(picture_header)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawPictureHeader *current)
{
int err;
HEADER("Picture Header");
ui(8, picture_start_code);
ui(10, temporal_reference);
uir(3, picture_coding_type);
ui(16, vbv_delay);
if (current->picture_coding_type == 2 ||
current->picture_coding_type == 3) {
ui(1, full_pel_forward_vector);
ui(3, forward_f_code);
}
if (current->picture_coding_type == 3) {
ui(1, full_pel_backward_vector);
ui(3, backward_f_code);
}
CHECK(FUNC(extra_information)(ctx, rw, &current->extra_information_picture,
"extra_information_picture[k]", "extra_bit_picture"));
return 0;
}
static int FUNC(picture_coding_extension)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawPictureCodingExtension *current)
{
CodedBitstreamMPEG2Context *mpeg2 = ctx->priv_data;
int err;
HEADER("Picture Coding Extension");
uir(4, f_code[0][0]);
uir(4, f_code[0][1]);
uir(4, f_code[1][0]);
uir(4, f_code[1][1]);
ui(2, intra_dc_precision);
ui(2, picture_structure);
ui(1, top_field_first);
ui(1, frame_pred_frame_dct);
ui(1, concealment_motion_vectors);
ui(1, q_scale_type);
ui(1, intra_vlc_format);
ui(1, alternate_scan);
ui(1, repeat_first_field);
ui(1, chroma_420_type);
ui(1, progressive_frame);
if (mpeg2->progressive_sequence) {
if (current->repeat_first_field) {
if (current->top_field_first)
mpeg2->number_of_frame_centre_offsets = 3;
else
mpeg2->number_of_frame_centre_offsets = 2;
} else {
mpeg2->number_of_frame_centre_offsets = 1;
}
} else {
if (current->picture_structure == 1 || // Top field.
current->picture_structure == 2) { // Bottom field.
mpeg2->number_of_frame_centre_offsets = 1;
} else {
if (current->repeat_first_field)
mpeg2->number_of_frame_centre_offsets = 3;
else
mpeg2->number_of_frame_centre_offsets = 2;
}
}
ui(1, composite_display_flag);
if (current->composite_display_flag) {
ui(1, v_axis);
ui(3, field_sequence);
ui(1, sub_carrier);
ui(7, burst_amplitude);
ui(8, sub_carrier_phase);
}
return 0;
}
static int FUNC(quant_matrix_extension)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawQuantMatrixExtension *current)
{
int err, i;
HEADER("Quant Matrix Extension");
ui(1, load_intra_quantiser_matrix);
if (current->load_intra_quantiser_matrix) {
for (i = 0; i < 64; i++)
uirs(8, intra_quantiser_matrix[i], 1, i);
}
ui(1, load_non_intra_quantiser_matrix);
if (current->load_non_intra_quantiser_matrix) {
for (i = 0; i < 64; i++)
uirs(8, non_intra_quantiser_matrix[i], 1, i);
}
ui(1, load_chroma_intra_quantiser_matrix);
if (current->load_chroma_intra_quantiser_matrix) {
for (i = 0; i < 64; i++)
uirs(8, intra_quantiser_matrix[i], 1, i);
}
ui(1, load_chroma_non_intra_quantiser_matrix);
if (current->load_chroma_non_intra_quantiser_matrix) {
for (i = 0; i < 64; i++)
uirs(8, chroma_non_intra_quantiser_matrix[i], 1, i);
}
return 0;
}
static int FUNC(picture_display_extension)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawPictureDisplayExtension *current)
{
CodedBitstreamMPEG2Context *mpeg2 = ctx->priv_data;
int err, i;
HEADER("Picture Display Extension");
for (i = 0; i < mpeg2->number_of_frame_centre_offsets; i++) {
sis(16, frame_centre_horizontal_offset[i], 1, i);
marker_bit();
sis(16, frame_centre_vertical_offset[i], 1, i);
marker_bit();
}
return 0;
}
static int FUNC(extension_data)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawExtensionData *current)
{
int err;
HEADER("Extension Data");
ui(8, extension_start_code);
ui(4, extension_start_code_identifier);
switch (current->extension_start_code_identifier) {
case MPEG2_EXTENSION_SEQUENCE:
return FUNC(sequence_extension)
(ctx, rw, &current->data.sequence);
case MPEG2_EXTENSION_SEQUENCE_DISPLAY:
return FUNC(sequence_display_extension)
(ctx, rw, &current->data.sequence_display);
case MPEG2_EXTENSION_QUANT_MATRIX:
return FUNC(quant_matrix_extension)
(ctx, rw, &current->data.quant_matrix);
case MPEG2_EXTENSION_PICTURE_DISPLAY:
return FUNC(picture_display_extension)
(ctx, rw, &current->data.picture_display);
case MPEG2_EXTENSION_PICTURE_CODING:
return FUNC(picture_coding_extension)
(ctx, rw, &current->data.picture_coding);
default:
av_log(ctx->log_ctx, AV_LOG_ERROR, "Extension ID %d not supported.\n",
current->extension_start_code_identifier);
return AVERROR_PATCHWELCOME;
}
}
static int FUNC(slice_header)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawSliceHeader *current)
{
CodedBitstreamMPEG2Context *mpeg2 = ctx->priv_data;
int err;
HEADER("Slice Header");
ui(8, slice_vertical_position);
if (mpeg2->vertical_size > 2800)
ui(3, slice_vertical_position_extension);
if (mpeg2->scalable) {
if (mpeg2->scalable_mode == 0)
ui(7, priority_breakpoint);
}
uir(5, quantiser_scale_code);
if (nextbits(1, 1, current->slice_extension_flag)) {
ui(1, slice_extension_flag);
ui(1, intra_slice);
ui(1, slice_picture_id_enable);
ui(6, slice_picture_id);
}
CHECK(FUNC(extra_information)(ctx, rw, &current->extra_information_slice,
"extra_information_slice[k]", "extra_bit_slice"));
return 0;
}
static int FUNC(sequence_end)(CodedBitstreamContext *ctx, RWContext *rw,
MPEG2RawSequenceEnd *current)
{
int err;
HEADER("Sequence End");
ui(8, sequence_end_code);
return 0;
}