[FFmpeg-devel] [PATCH 06/20] lavc: Add coded bitstream read/write support for MPEG-2
Mark Thompson
sw at jkqxz.net
Sun Oct 15 18:04:33 EEST 2017
(cherry picked from commit 2bc9ba8d3c41f3a8e56484bd67b05040c7909a01)
(cherry picked from commit a41b69b5eb950c10d8ede472bcc4e88ce4246db9)
---
configure | 2 +
libavcodec/Makefile | 1 +
libavcodec/cbs.c | 3 +
libavcodec/cbs.h | 1 +
libavcodec/cbs_internal.h | 1 +
libavcodec/cbs_mpeg2.c | 414 +++++++++++++++++++++++++++++++++
libavcodec/cbs_mpeg2.h | 224 ++++++++++++++++++
libavcodec/cbs_mpeg2_syntax_template.c | 384 ++++++++++++++++++++++++++++++
8 files changed, 1030 insertions(+)
create mode 100644 libavcodec/cbs_mpeg2.c
create mode 100644 libavcodec/cbs_mpeg2.h
create mode 100644 libavcodec/cbs_mpeg2_syntax_template.c
diff --git a/configure b/configure
index c6c1206073..7ef922c27b 100755
--- a/configure
+++ b/configure
@@ -2153,6 +2153,7 @@ CONFIG_EXTRA="
cbs
cbs_h264
cbs_h265
+ cbs_mpeg2
dirac_parse
dvprofile
exif
@@ -2408,6 +2409,7 @@ threads_if_any="$THREADS_LIST"
# subsystems
cbs_h264_select="cbs golomb"
cbs_h265_select="cbs golomb"
+cbs_mpeg2_select="cbs"
dct_select="rdft"
dirac_parse_select="golomb"
error_resilience_select="me_cmp"
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 39b7dd1e2f..0265c92130 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -62,6 +62,7 @@ OBJS-$(CONFIG_CABAC) += cabac.o
OBJS-$(CONFIG_CBS) += cbs.o
OBJS-$(CONFIG_CBS_H264) += cbs_h2645.o h2645_parse.o
OBJS-$(CONFIG_CBS_H265) += cbs_h2645.o h2645_parse.o
+OBJS-$(CONFIG_CBS_MPEG2) += cbs_mpeg2.o
OBJS-$(CONFIG_CRYSTALHD) += crystalhd.o
OBJS-$(CONFIG_DCT) += dct.o dct32_fixed.o dct32_float.o
OBJS-$(CONFIG_ERROR_RESILIENCE) += error_resilience.o
diff --git a/libavcodec/cbs.c b/libavcodec/cbs.c
index d7eb3033c4..97ab520c22 100644
--- a/libavcodec/cbs.c
+++ b/libavcodec/cbs.c
@@ -34,6 +34,9 @@ static const CodedBitstreamType *cbs_type_table[] = {
#if CONFIG_CBS_H265
&ff_cbs_type_h265,
#endif
+#if CONFIG_CBS_MPEG2
+ &ff_cbs_type_mpeg2,
+#endif
};
int ff_cbs_init(CodedBitstreamContext **ctx_ptr,
diff --git a/libavcodec/cbs.h b/libavcodec/cbs.h
index a367fd0bf6..ff97880610 100644
--- a/libavcodec/cbs.h
+++ b/libavcodec/cbs.h
@@ -45,6 +45,7 @@ struct CodedBitstreamType;
*
* H.264 / AVC: nal_unit_type
* H.265 / HEVC: nal_unit_type
+ * MPEG-2: start code value (without prefix)
*/
typedef uint32_t CodedBitstreamUnitType;
diff --git a/libavcodec/cbs_internal.h b/libavcodec/cbs_internal.h
index f8263bef0a..ae0b417b43 100644
--- a/libavcodec/cbs_internal.h
+++ b/libavcodec/cbs_internal.h
@@ -85,6 +85,7 @@ int ff_cbs_write_unsigned(CodedBitstreamContext *ctx, PutBitContext *pbc,
extern const CodedBitstreamType ff_cbs_type_h264;
extern const CodedBitstreamType ff_cbs_type_h265;
+extern const CodedBitstreamType ff_cbs_type_mpeg2;
#endif /* AVCODEC_CBS_INTERNAL_H */
diff --git a/libavcodec/cbs_mpeg2.c b/libavcodec/cbs_mpeg2.c
new file mode 100644
index 0000000000..d137762227
--- /dev/null
+++ b/libavcodec/cbs_mpeg2.c
@@ -0,0 +1,414 @@
+/*
+ * 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
+ */
+
+#include "libavutil/avassert.h"
+
+#include "cbs.h"
+#include "cbs_internal.h"
+#include "cbs_mpeg2.h"
+#include "internal.h"
+
+
+#define HEADER(name) do { \
+ ff_cbs_trace_header(ctx, name); \
+ } while (0)
+
+#define CHECK(call) do { \
+ err = (call); \
+ if (err < 0) \
+ return err; \
+ } while (0)
+
+#define FUNC_NAME(rw, codec, name) cbs_ ## codec ## _ ## rw ## _ ## name
+#define FUNC_MPEG2(rw, name) FUNC_NAME(rw, mpeg2, name)
+#define FUNC(name) FUNC_MPEG2(READWRITE, name)
+
+
+#define READ
+#define READWRITE read
+#define RWContext GetBitContext
+
+#define xui(width, name, var) do { \
+ uint32_t value = 0; \
+ CHECK(ff_cbs_read_unsigned(ctx, rw, width, #name, \
+ &value, 0, (1 << width) - 1)); \
+ var = value; \
+ } while (0)
+
+#define ui(width, name) \
+ xui(width, name, current->name)
+
+#define marker_bit() do { \
+ av_unused int one = 1; \
+ CHECK(ff_cbs_read_unsigned(ctx, rw, 1, "marker_bit", &one, 1, 1)); \
+ } while (0)
+
+#define nextbits(width, compare, var) \
+ (get_bits_left(rw) >= width && \
+ (var = show_bits(rw, width)) == (compare))
+
+#include "cbs_mpeg2_syntax_template.c"
+
+#undef READ
+#undef READWRITE
+#undef RWContext
+#undef xui
+#undef ui
+#undef marker_bit
+#undef nextbits
+
+
+#define WRITE
+#define READWRITE write
+#define RWContext PutBitContext
+
+#define xui(width, name, var) do { \
+ CHECK(ff_cbs_write_unsigned(ctx, rw, width, #name, \
+ var, 0, (1 << width) - 1)); \
+ } while (0)
+
+#define ui(width, name) \
+ xui(width, name, current->name)
+
+#define marker_bit() do { \
+ CHECK(ff_cbs_write_unsigned(ctx, rw, 1, "marker_bit", 1, 1, 1)); \
+ } while (0)
+
+#define nextbits(width, compare, var) (var)
+
+#include "cbs_mpeg2_syntax_template.c"
+
+#undef READ
+#undef READWRITE
+#undef RWContext
+#undef xui
+#undef ui
+#undef marker_bit
+#undef nextbits
+
+
+static int cbs_mpeg2_split_fragment(CodedBitstreamContext *ctx,
+ CodedBitstreamFragment *frag,
+ int header)
+{
+ const uint8_t *start, *end;
+ uint8_t *unit_data;
+ uint32_t start_code = -1, next_start_code = -1;
+ size_t unit_size;
+ int err, i, unit_type;
+
+ start = avpriv_find_start_code(frag->data, frag->data + frag->data_size,
+ &start_code);
+ for (i = 0;; i++) {
+ end = avpriv_find_start_code(start, frag->data + frag->data_size,
+ &next_start_code);
+
+ unit_type = start_code & 0xff;
+
+ // The start and end pointers point at to the byte following the
+ // start_code_identifier in the start code that they found.
+ if (end == frag->data + frag->data_size) {
+ // We didn't find a start code, so this is the final unit.
+ unit_size = end - (start - 1);
+ } else {
+ // Unit runs from start to the beginning of the start code
+ // pointed to by end (including any padding zeroes).
+ unit_size = (end - 4) - (start - 1);
+ }
+
+ unit_data = av_malloc(unit_size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!unit_data)
+ return AVERROR(ENOMEM);
+ memcpy(unit_data, start - 1, unit_size);
+ memset(unit_data + unit_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
+
+ err = ff_cbs_insert_unit_data(ctx, frag, i, unit_type,
+ unit_data, unit_size);
+ if (err < 0) {
+ av_freep(&unit_data);
+ return err;
+ }
+
+ if (end == frag->data + frag->data_size)
+ break;
+
+ start_code = next_start_code;
+ start = end;
+ }
+
+ return 0;
+}
+
+static int cbs_mpeg2_read_unit(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit)
+{
+ GetBitContext gbc;
+ int err;
+
+ err = init_get_bits(&gbc, unit->data, 8 * unit->data_size);
+ if (err < 0)
+ return err;
+
+ if (MPEG2_START_IS_SLICE(unit->type)) {
+ MPEG2RawSlice *slice;
+ int pos, len;
+
+ slice = av_mallocz(sizeof(*slice));
+ if (!slice)
+ return AVERROR(ENOMEM);
+ err = cbs_mpeg2_read_slice_header(ctx, &gbc, &slice->header);
+ if (err < 0) {
+ av_free(slice);
+ return err;
+ }
+
+ pos = get_bits_count(&gbc);
+ len = unit->data_size;
+
+ slice->data_size = len - pos / 8;
+ slice->data = av_malloc(slice->data_size +
+ AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!slice->data) {
+ av_free(slice);
+ return AVERROR(ENOMEM);
+ }
+
+ memcpy(slice->data,
+ unit->data + pos / 8, slice->data_size);
+ memset(slice->data + slice->data_size, 0,
+ AV_INPUT_BUFFER_PADDING_SIZE);
+ slice->data_bit_start = pos % 8;
+
+ unit->content = slice;
+
+ } else {
+ switch (unit->type) {
+#define START(start_code, type, func) \
+ case start_code: \
+ { \
+ type *header; \
+ header = av_mallocz(sizeof(*header)); \
+ if (!header) \
+ return AVERROR(ENOMEM); \
+ err = cbs_mpeg2_read_ ## func(ctx, &gbc, header); \
+ if (err < 0) { \
+ av_free(header); \
+ return err; \
+ } \
+ unit->content = header; \
+ } \
+ break;
+ START(0x00, MPEG2RawPictureHeader, picture_header);
+ START(0xb2, MPEG2RawUserData, user_data);
+ START(0xb3, MPEG2RawSequenceHeader, sequence_header);
+ START(0xb5, MPEG2RawExtensionData, extension_data);
+ START(0xb8, MPEG2RawGroupOfPicturesHeader, group_of_pictures_header);
+#undef START
+ default:
+ av_log(ctx->log_ctx, AV_LOG_ERROR, "Unknown start code %02x.\n",
+ unit->type);
+ return AVERROR_INVALIDDATA;
+ }
+ }
+
+ return 0;
+}
+
+static int cbs_mpeg2_write_header(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit,
+ PutBitContext *pbc)
+{
+ int err;
+
+ switch (unit->type) {
+#define START(start_code, type, func) \
+ case start_code: \
+ err = cbs_mpeg2_write_ ## func(ctx, pbc, unit->content); \
+ break;
+ START(0x00, MPEG2RawPictureHeader, picture_header);
+ START(0xb2, MPEG2RawUserData, user_data);
+ START(0xb3, MPEG2RawSequenceHeader, sequence_header);
+ START(0xb5, MPEG2RawExtensionData, extension_data);
+ START(0xb8, MPEG2RawGroupOfPicturesHeader, group_of_pictures_header);
+#undef START
+ default:
+ av_log(ctx->log_ctx, AV_LOG_ERROR, "Write unimplemented for start "
+ "code %02"PRIu32".\n", unit->type);
+ return AVERROR_PATCHWELCOME;
+ }
+
+ return err;
+}
+
+static int cbs_mpeg2_write_slice(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit,
+ PutBitContext *pbc)
+{
+ MPEG2RawSlice *slice = unit->content;
+ GetBitContext gbc;
+ size_t bits_left;
+ int err;
+
+ err = cbs_mpeg2_write_slice_header(ctx, pbc, &slice->header);
+ if (err < 0)
+ return err;
+
+ if (slice->data) {
+ if (slice->data_size * 8 + 8 > put_bits_left(pbc))
+ return AVERROR(ENOSPC);
+
+ init_get_bits(&gbc, slice->data, slice->data_size * 8);
+ skip_bits_long(&gbc, slice->data_bit_start);
+
+ while (get_bits_left(&gbc) > 15)
+ put_bits(pbc, 16, get_bits(&gbc, 16));
+
+ bits_left = get_bits_left(&gbc);
+ put_bits(pbc, bits_left, get_bits(&gbc, bits_left));
+
+ // Align with zeroes.
+ while (put_bits_count(pbc) % 8 != 0)
+ put_bits(pbc, 1, 0);
+ }
+
+ return 0;
+}
+
+static int cbs_mpeg2_write_unit(CodedBitstreamContext *ctx,
+ CodedBitstreamUnit *unit)
+{
+ CodedBitstreamMPEG2Context *priv = ctx->priv_data;
+ PutBitContext pbc;
+ int err;
+
+ if (!priv->write_buffer) {
+ // Initial write buffer size is 1MB.
+ priv->write_buffer_size = 1024 * 1024;
+
+ reallocate_and_try_again:
+ err = av_reallocp(&priv->write_buffer, priv->write_buffer_size);
+ if (err < 0) {
+ av_log(ctx->log_ctx, AV_LOG_ERROR, "Unable to allocate a "
+ "sufficiently large write buffer (last attempt "
+ "%zu bytes).\n", priv->write_buffer_size);
+ return err;
+ }
+ }
+
+ init_put_bits(&pbc, priv->write_buffer, priv->write_buffer_size);
+
+ if (unit->type >= 0x01 && unit->type <= 0xaf)
+ err = cbs_mpeg2_write_slice(ctx, unit, &pbc);
+ else
+ err = cbs_mpeg2_write_header(ctx, unit, &pbc);
+
+ if (err == AVERROR(ENOSPC)) {
+ // Overflow.
+ priv->write_buffer_size *= 2;
+ goto reallocate_and_try_again;
+ }
+ if (err < 0) {
+ // Write failed for some other reason.
+ return err;
+ }
+
+ if (put_bits_count(&pbc) % 8)
+ unit->data_bit_padding = 8 - put_bits_count(&pbc) % 8;
+ else
+ unit->data_bit_padding = 0;
+
+ unit->data_size = (put_bits_count(&pbc) + 7) / 8;
+ flush_put_bits(&pbc);
+
+ err = av_reallocp(&unit->data, unit->data_size);
+ if (err < 0)
+ return err;
+
+ memcpy(unit->data, priv->write_buffer, unit->data_size);
+
+ return 0;
+}
+
+static int cbs_mpeg2_assemble_fragment(CodedBitstreamContext *ctx,
+ CodedBitstreamFragment *frag)
+{
+ uint8_t *data;
+ size_t size, dp, sp;
+ int i;
+
+ size = 0;
+ for (i = 0; i < frag->nb_units; i++)
+ size += 3 + frag->units[i].data_size;
+
+ data = av_malloc(size);
+ if (!data)
+ return AVERROR(ENOMEM);
+
+ dp = 0;
+ for (i = 0; i < frag->nb_units; i++) {
+ CodedBitstreamUnit *unit = &frag->units[i];
+
+ data[dp++] = 0;
+ data[dp++] = 0;
+ data[dp++] = 1;
+
+ for (sp = 0; sp < unit->data_size; sp++)
+ data[dp++] = unit->data[sp];
+ }
+
+ av_assert0(dp == size);
+
+ frag->data = data;
+ frag->data_size = size;
+
+ return 0;
+}
+
+static void cbs_mpeg2_free_unit(CodedBitstreamUnit *unit)
+{
+ if (MPEG2_START_IS_SLICE(unit->type)) {
+ MPEG2RawSlice *slice = unit->content;
+ av_freep(&slice->data);
+ av_freep(&slice->header.extra_information);
+ } else if (unit->type == MPEG2_START_USER_DATA) {
+ MPEG2RawUserData *user = unit->content;
+ av_freep(&user->user_data);
+ }
+ av_freep(&unit->content);
+}
+
+static void cbs_mpeg2_close(CodedBitstreamContext *ctx)
+{
+ CodedBitstreamMPEG2Context *priv = ctx->priv_data;
+
+ av_freep(&priv->write_buffer);
+}
+
+const CodedBitstreamType ff_cbs_type_mpeg2 = {
+ .codec_id = AV_CODEC_ID_MPEG2VIDEO,
+
+ .priv_data_size = sizeof(CodedBitstreamMPEG2Context),
+
+ .split_fragment = &cbs_mpeg2_split_fragment,
+ .read_unit = &cbs_mpeg2_read_unit,
+ .write_unit = &cbs_mpeg2_write_unit,
+ .assemble_fragment = &cbs_mpeg2_assemble_fragment,
+
+ .free_unit = &cbs_mpeg2_free_unit,
+ .close = &cbs_mpeg2_close,
+};
diff --git a/libavcodec/cbs_mpeg2.h b/libavcodec/cbs_mpeg2.h
new file mode 100644
index 0000000000..a8f12b2e75
--- /dev/null
+++ b/libavcodec/cbs_mpeg2.h
@@ -0,0 +1,224 @@
+/*
+ * 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
+ */
+
+#ifndef AVCODEC_CBS_MPEG2_H
+#define AVCODEC_CBS_MPEG2_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+
+enum {
+ MPEG2_START_PICTURE = 0x00,
+ MPEG2_START_SLICE_MIN = 0x01,
+ MPEG2_START_SLICE_MAX = 0xaf,
+ MPEG2_START_USER_DATA = 0xb2,
+ MPEG2_START_SEQUENCE_HEADER = 0xb3,
+ MPEG2_START_SEQUENCE_ERROR = 0xb4,
+ MPEG2_START_EXTENSION = 0xb5,
+ MPEG2_START_SEQUENCE_END = 0xb7,
+ MPEG2_START_GROUP = 0xb8,
+};
+
+#define MPEG2_START_IS_SLICE(type) \
+ ((type) >= MPEG2_START_SLICE_MIN && \
+ (type) <= MPEG2_START_SLICE_MAX)
+
+enum {
+ MPEG2_EXTENSION_SEQUENCE = 0x1,
+ MPEG2_EXTENSION_SEQUENCE_DISPLAY = 0x2,
+ MPEG2_EXTENSION_QUANT_MATRIX = 0x3,
+ MPEG2_EXTENSION_COPYRIGHT = 0x4,
+ MPEG2_EXTENSION_SEQUENCE_SCALABLE = 0x5,
+ MPEG2_EXTENSION_PICTURE_DISPLAY = 0x7,
+ MPEG2_EXTENSION_PICTURE_CODING = 0x8,
+ MPEG2_EXTENSION_PICTURE_SPATIAL_SCALABLE = 0x9,
+ MPEG2_EXTENSION_PICTURE_TEMPORAL_SCALABLE = 0xa,
+ MPEG2_EXTENSION_CAMAERA_PARAMETERS = 0xb,
+ MPEG2_EXTENSION_ITU_T = 0xc,
+};
+
+
+typedef struct MPEG2RawSequenceHeader {
+ uint8_t sequence_header_code;
+
+ uint16_t horizontal_size_value;
+ uint16_t vertical_size_value;
+ uint8_t aspect_ratio_information;
+ uint8_t frame_rate_code;
+ uint32_t bit_rate_value;
+ uint16_t vbv_buffer_size_value;
+ uint8_t constrained_parameters_flag;
+
+ uint8_t load_intra_quantiser_matrix;
+ uint8_t intra_quantiser_matrix[64];
+ uint8_t load_non_intra_quantiser_matrix;
+ uint8_t non_intra_quantiser_matrix[64];
+} MPEG2RawSequenceHeader;
+
+typedef struct MPEG2RawUserData {
+ uint8_t user_data_start_code;
+
+ uint8_t *user_data;
+ size_t user_data_length;
+} MPEG2RawUserData;
+
+typedef struct MPEG2RawSequenceExtension {
+ uint8_t profile_and_level_indication;
+ uint8_t progressive_sequence;
+ uint8_t chroma_format;
+ uint8_t horizontal_size_extension;
+ uint8_t vertical_size_extension;
+ uint16_t bit_rate_extension;
+ uint8_t vbv_buffer_size_extension;
+ uint8_t low_delay;
+ uint8_t frame_rate_extension_n;
+ uint8_t frame_rate_extension_d;
+} MPEG2RawSequenceExtension;
+
+typedef struct MPEG2RawSequenceDisplayExtension {
+ uint8_t video_format;
+
+ uint8_t colour_description;
+ uint8_t colour_primaries;
+ uint8_t transfer_characteristics;
+ uint8_t matrix_coefficients;
+
+ uint16_t display_horizontal_size;
+ uint16_t display_vertical_size;
+} MPEG2RawSequenceDisplayExtension;
+
+typedef struct MPEG2RawGroupOfPicturesHeader {
+ uint8_t group_start_code;
+
+ uint32_t time_code;
+ uint8_t closed_gop;
+ uint8_t broken_link;
+} MPEG2RawGroupOfPicturesHeader;
+
+typedef struct MPEG2RawPictureHeader {
+ uint8_t picture_start_code;
+
+ uint16_t temporal_reference;
+ uint8_t picture_coding_type;
+ uint16_t vbv_delay;
+
+ uint8_t full_pel_forward_vector;
+ uint8_t forward_f_code;
+ uint8_t full_pel_backward_vector;
+ uint8_t backward_f_code;
+
+ uint8_t extra_bit_picture;
+} MPEG2RawPictureHeader;
+
+typedef struct MPEG2RawPictureCodingExtension {
+ uint8_t f_code[2][2];
+
+ uint8_t intra_dc_precision;
+ uint8_t picture_structure;
+ uint8_t top_field_first;
+ uint8_t frame_pred_frame_dct;
+ uint8_t concealment_motion_vectors;
+ uint8_t q_scale_type;
+ uint8_t intra_vlc_format;
+ uint8_t alternate_scan;
+ uint8_t repeat_first_field;
+ uint8_t chroma_420_type;
+ uint8_t progressive_frame;
+
+ uint8_t composite_display_flag;
+ uint8_t v_axis;
+ uint8_t field_sequence;
+ uint8_t sub_carrier;
+ uint8_t burst_amplitude;
+ uint8_t sub_carrier_phase;
+} MPEG2RawPictureCodingExtension;
+
+typedef struct MPEG2RawQuantMatrixExtension {
+ uint8_t load_intra_quantiser_matrix;
+ uint8_t intra_quantiser_matrix[64];
+ uint8_t load_non_intra_quantiser_matrix;
+ uint8_t non_intra_quantiser_matrix[64];
+ uint8_t load_chroma_intra_quantiser_matrix;
+ uint8_t chroma_intra_quantiser_matrix[64];
+ uint8_t load_chroma_non_intra_quantiser_matrix;
+ uint8_t chroma_non_intra_quantiser_matrix[64];
+} MPEG2RawQuantMatrixExtension;
+
+typedef struct MPEG2RawPictureDisplayExtension {
+ uint16_t frame_centre_horizontal_offset[3];
+ uint16_t frame_centre_vertical_offset[3];
+} MPEG2RawPictureDisplayExtension;
+
+typedef struct MPEG2RawExtensionData {
+ uint8_t extension_start_code;
+ uint8_t extension_start_code_identifier;
+
+ union {
+ MPEG2RawSequenceExtension sequence;
+ MPEG2RawSequenceDisplayExtension sequence_display;
+ MPEG2RawQuantMatrixExtension quant_matrix;
+ MPEG2RawPictureCodingExtension picture_coding;
+ MPEG2RawPictureDisplayExtension picture_display;
+ } data;
+} MPEG2RawExtensionData;
+
+typedef struct MPEG2RawSliceHeader {
+ uint8_t slice_vertical_position;
+
+ uint8_t slice_vertical_position_extension;
+ uint8_t priority_breakpoint;
+
+ uint8_t quantiser_scale_code;
+
+ uint8_t slice_extension_flag;
+ uint8_t intra_slice;
+ uint8_t slice_picture_id_enable;
+ uint8_t slice_picture_id;
+
+ uint8_t extra_bit_slice;
+
+ size_t extra_information_length;
+ uint8_t *extra_information;
+} MPEG2RawSliceHeader;
+
+typedef struct MPEG2RawSlice {
+ MPEG2RawSliceHeader header;
+
+ uint8_t *data;
+ size_t data_size;
+ int data_bit_start;
+} MPEG2RawSlice;
+
+
+typedef struct CodedBitstreamMPEG2Context {
+ // Elements stored in headers which are required for other decoding.
+ uint16_t horizontal_size;
+ uint16_t vertical_size;
+ uint8_t scalable;
+ uint8_t scalable_mode;
+ uint8_t progressive_sequence;
+ uint8_t number_of_frame_centre_offsets;
+
+ // Write buffer.
+ uint8_t *write_buffer;
+ size_t write_buffer_size;
+} CodedBitstreamMPEG2Context;
+
+
+#endif /* AVCODEC_CBS_MPEG2_H */
diff --git a/libavcodec/cbs_mpeg2_syntax_template.c b/libavcodec/cbs_mpeg2_syntax_template.c
new file mode 100644
index 0000000000..90dde26aed
--- /dev/null
+++ b/libavcodec/cbs_mpeg2_syntax_template.c
@@ -0,0 +1,384 @@
+/*
+ * 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);
+
+ ui(12, horizontal_size_value);
+ ui(12, vertical_size_value);
+
+ mpeg2->horizontal_size = current->horizontal_size_value;
+ mpeg2->vertical_size = current->vertical_size_value;
+
+ ui(4, aspect_ratio_information);
+ ui(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++)
+ ui(8, intra_quantiser_matrix[i]);
+ }
+
+ ui(1, load_non_intra_quantiser_matrix);
+ if (current->load_non_intra_quantiser_matrix) {
+ for (i = 0; i < 64; i++)
+ ui(8, non_intra_quantiser_matrix[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 = av_malloc(k);
+ if (!current->user_data)
+ return AVERROR(ENOMEM);
+ }
+#endif
+
+ for (k = 0; k < current->user_data_length; k++)
+ xui(8, user_data, current->user_data[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) {
+ ui(8, colour_primaries);
+ ui(8, transfer_characteristics);
+ ui(8, matrix_coefficients);
+ }
+
+ 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(picture_header)(CodedBitstreamContext *ctx, RWContext *rw,
+ MPEG2RawPictureHeader *current)
+{
+ int err;
+
+ HEADER("Picture Header");
+
+ ui(8, picture_start_code);
+
+ ui(10, temporal_reference);
+ ui(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);
+ }
+
+ ui(1, 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");
+
+ ui(4, f_code[0][0]);
+ ui(4, f_code[0][1]);
+ ui(4, f_code[1][0]);
+ ui(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++)
+ ui(8, intra_quantiser_matrix[i]);
+ }
+
+ ui(1, load_non_intra_quantiser_matrix);
+ if (current->load_non_intra_quantiser_matrix) {
+ for (i = 0; i < 64; i++)
+ ui(8, non_intra_quantiser_matrix[i]);
+ }
+
+ ui(1, load_chroma_intra_quantiser_matrix);
+ if (current->load_chroma_intra_quantiser_matrix) {
+ for (i = 0; i < 64; i++)
+ ui(8, intra_quantiser_matrix[i]);
+ }
+
+ ui(1, load_chroma_non_intra_quantiser_matrix);
+ if (current->load_chroma_non_intra_quantiser_matrix) {
+ for (i = 0; i < 64; i++)
+ ui(8, chroma_non_intra_quantiser_matrix[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++) {
+ ui(16, frame_centre_horizontal_offset[i]);
+ marker_bit();
+ ui(16, frame_centre_vertical_offset[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 1:
+ return FUNC(sequence_extension)
+ (ctx, rw, ¤t->data.sequence);
+ case 2:
+ return FUNC(sequence_display_extension)
+ (ctx, rw, ¤t->data.sequence_display);
+ case 3:
+ return FUNC(quant_matrix_extension)
+ (ctx, rw, ¤t->data.quant_matrix);
+ case 7:
+ return FUNC(picture_display_extension)
+ (ctx, rw, ¤t->data.picture_display);
+ case 8:
+ return FUNC(picture_coding_extension)
+ (ctx, rw, ¤t->data.picture_coding);
+ default:
+ av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid extension ID %d.\n",
+ current->extension_start_code_identifier);
+ return AVERROR_INVALIDDATA;
+ }
+}
+
+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);
+ }
+
+ ui(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);
+
+ {
+ size_t k;
+#ifdef READ
+ GetBitContext start;
+ uint8_t bit;
+ start = *rw;
+ for (k = 0; nextbits(1, 1, bit); k++)
+ skip_bits(rw, 8);
+ current->extra_information_length = k;
+ if (k > 0) {
+ *rw = start;
+ current->extra_information =
+ av_malloc(current->extra_information_length);
+ if (!current->extra_information)
+ return AVERROR(ENOMEM);
+ for (k = 0; k < current->extra_information_length; k++) {
+ xui(1, extra_bit_slice, bit);
+ xui(8, extra_information_slice,
+ current->extra_information[k]);
+ }
+ }
+#else
+ for (k = 0; k < current->extra_information_length; k++) {
+ xui(1, extra_bit_slice, 1);
+ xui(8, extra_information_slice, current->extra_information[k]);
+ }
+#endif
+ }
+ }
+ ui(1, extra_bit_slice);
+
+ return 0;
+}
--
2.11.0
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