/*
* AV1 helper functions for muxers
* Copyright (c) 2018 James Almer <jamrial@gmail.com>
*
* 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/mem.h"
#include "libavcodec/av1.h"
#include "libavcodec/av1_parse.h"
#include "libavcodec/profiles.h"
#include "libavcodec/put_bits.h"
#include "av1.h"
#include "avio.h"
int ff_av1_filter_obus(AVIOContext *pb, const uint8_t *buf, int size)
{
const uint8_t *end = buf + size;
int64_t obu_size;
int start_pos, type, temporal_id, spatial_id;
size = 0;
while (buf < end) {
int len = parse_obu_header(buf, end - buf, &obu_size, &start_pos,
&type, &temporal_id, &spatial_id);
if (len < 0)
return len;
switch (type) {
case AV1_OBU_TEMPORAL_DELIMITER:
case AV1_OBU_REDUNDANT_FRAME_HEADER:
case AV1_OBU_TILE_LIST:
case AV1_OBU_PADDING:
break;
default:
avio_write(pb, buf, len);
size += len;
break;
}
buf += len;
}
return size;
}
int ff_av1_filter_obus_buf(const uint8_t *buf, uint8_t **out, int *size)
{
AVIOContext *pb;
int ret;
ret = avio_open_dyn_buf(&pb);
if (ret < 0)
return ret;
ret = ff_av1_filter_obus(pb, buf, *size);
if (ret < 0)
return ret;
av_freep(out);
*size = avio_close_dyn_buf(pb, out);
return ret;
}
typedef struct AV1SequenceParameters {
uint8_t seq_profile;
uint8_t seq_level_idx_0;
uint8_t seq_tier_0;
uint8_t high_bitdepth;
uint8_t twelve_bit;
uint8_t monochrome;
uint8_t chroma_subsampling_x;
uint8_t chroma_subsampling_y;
uint8_t chroma_sample_position;
} AV1SequenceParameters;
static inline void uvlc(GetBitContext *gb)
{
int leading_zeros = 0;
while (get_bits_left(gb)) {
if (get_bits1(gb))
break;
leading_zeros++;
}
if (leading_zeros >= 32)
return;
skip_bits_long(gb, leading_zeros);
}
static int parse_color_config(AV1SequenceParameters *seq_params, GetBitContext *gb)
{
int color_primaries, transfer_characteristics, matrix_coefficients;
seq_params->high_bitdepth = get_bits1(gb);
if (seq_params->seq_profile == FF_PROFILE_AV1_PROFESSIONAL && seq_params->high_bitdepth)
seq_params->twelve_bit = get_bits1(gb);
if (seq_params->seq_profile == FF_PROFILE_AV1_HIGH)
seq_params->monochrome = 0;
else
seq_params->monochrome = get_bits1(gb);
if (get_bits1(gb)) { // color_description_present_flag
color_primaries = get_bits(gb, 8);
transfer_characteristics = get_bits(gb, 8);
matrix_coefficients = get_bits(gb, 8);
} else {
color_primaries = AVCOL_PRI_UNSPECIFIED;
transfer_characteristics = AVCOL_TRC_UNSPECIFIED;
matrix_coefficients = AVCOL_SPC_UNSPECIFIED;
}
if (seq_params->monochrome) {
skip_bits1(gb); // color_range
seq_params->chroma_subsampling_x = 1;
seq_params->chroma_subsampling_y = 1;
seq_params->chroma_sample_position = 0;
return 0;
} else if (color_primaries == AVCOL_PRI_BT709 &&
transfer_characteristics == AVCOL_TRC_IEC61966_2_1 &&
matrix_coefficients == AVCOL_SPC_RGB) {
seq_params->chroma_subsampling_x = 0;
seq_params->chroma_subsampling_y = 0;
} else {
skip_bits1(gb); // color_range
if (seq_params->seq_profile == FF_PROFILE_AV1_MAIN) {
seq_params->chroma_subsampling_x = 1;
seq_params->chroma_subsampling_y = 1;
} else if (seq_params->seq_profile == FF_PROFILE_AV1_HIGH) {
seq_params->chroma_subsampling_x = 0;
seq_params->chroma_subsampling_y = 0;
} else {
if (seq_params->twelve_bit) {
seq_params->chroma_subsampling_x = get_bits1(gb);
if (seq_params->chroma_subsampling_x)
seq_params->chroma_subsampling_y = get_bits1(gb);
else
seq_params->chroma_subsampling_y = 0;
} else {
seq_params->chroma_subsampling_x = 1;
seq_params->chroma_subsampling_y = 0;
}
}
if (seq_params->chroma_subsampling_x && seq_params->chroma_subsampling_y)
seq_params->chroma_sample_position = get_bits(gb, 2);
}
skip_bits1(gb); // separate_uv_delta_q
return 0;
}
static int parse_sequence_header(AV1SequenceParameters *seq_params, const uint8_t *buf, int size)
{
GetBitContext gb;
int reduced_still_picture_header;
int frame_width_bits_minus_1, frame_height_bits_minus_1;
int size_bits, ret;
size_bits = get_obu_bit_length(buf, size, AV1_OBU_SEQUENCE_HEADER);
if (size_bits < 0)
return size_bits;
ret = init_get_bits(&gb, buf, size_bits);
if (ret < 0)
return ret;
memset(seq_params, 0, sizeof(*seq_params));
seq_params->seq_profile = get_bits(&gb, 3);
skip_bits1(&gb); // still_picture
reduced_still_picture_header = get_bits1(&gb);
if (reduced_still_picture_header) {
seq_params->seq_level_idx_0 = get_bits(&gb, 5);
seq_params->seq_tier_0 = 0;
} else {
int initial_display_delay_present_flag, operating_points_cnt_minus_1;
int decoder_model_info_present_flag, buffer_delay_length_minus_1;
if (get_bits1(&gb)) { // timing_info_present_flag
skip_bits_long(&gb, 32); // num_units_in_display_tick
skip_bits_long(&gb, 32); // time_scale
if (get_bits1(&gb)) // equal_picture_interval
uvlc(&gb); // num_ticks_per_picture_minus_1
decoder_model_info_present_flag = get_bits1(&gb);
if (decoder_model_info_present_flag) {
buffer_delay_length_minus_1 = get_bits(&gb, 5);
skip_bits_long(&gb, 32); // num_units_in_decoding_tick
skip_bits(&gb, 10); // buffer_removal_time_length_minus_1 (5)
// frame_presentation_time_length_minus_1 (5)
}
} else
decoder_model_info_present_flag = 0;
initial_display_delay_present_flag = get_bits1(&gb);
operating_points_cnt_minus_1 = get_bits(&gb, 5);
for (int i = 0; i <= operating_points_cnt_minus_1; i++) {
int seq_level_idx, seq_tier;
skip_bits(&gb, 12); // operating_point_idc
seq_level_idx = get_bits(&gb, 5);
if (seq_level_idx > 7)
seq_tier = get_bits1(&gb);
else
seq_tier = 0;
if (decoder_model_info_present_flag) {
if (get_bits1(&gb)) { // decoder_model_present_for_this_op
skip_bits_long(&gb, buffer_delay_length_minus_1 + 1); // decoder_buffer_delay
skip_bits_long(&gb, buffer_delay_length_minus_1 + 1); // encoder_buffer_delay
skip_bits1(&gb); // low_delay_mode_flag
}
}
if (initial_display_delay_present_flag) {
if (get_bits1(&gb)) // initial_display_delay_present_for_this_op
skip_bits(&gb, 4); // initial_display_delay_minus_1
}
if (i == 0) {
seq_params->seq_level_idx_0 = seq_level_idx;
seq_params->seq_tier_0 = seq_tier;
}
}
}
frame_width_bits_minus_1 = get_bits(&gb, 4);
frame_height_bits_minus_1 = get_bits(&gb, 4);
skip_bits(&gb, frame_width_bits_minus_1 + 1); // max_frame_width_minus_1
skip_bits(&gb, frame_height_bits_minus_1 + 1); // max_frame_height_minus_1
if (!reduced_still_picture_header) {
if (get_bits1(&gb)) // frame_id_numbers_present_flag
skip_bits(&gb, 7); // delta_frame_id_length_minus_2 (4), additional_frame_id_length_minus_1 (3)
}
skip_bits(&gb, 3); // use_128x128_superblock (1), enable_filter_intra (1), enable_intra_edge_filter (1)
if (!reduced_still_picture_header) {
int enable_order_hint, seq_force_screen_content_tools;
skip_bits(&gb, 4); // enable_intraintra_compound (1), enable_masked_compound (1)
// enable_warped_motion (1), enable_dual_filter (1)
enable_order_hint = get_bits1(&gb);
if (enable_order_hint)
skip_bits(&gb, 2); // enable_jnt_comp (1), enable_ref_frame_mvs (1)
if (get_bits1(&gb)) // seq_choose_screen_content_tools
seq_force_screen_content_tools = 2;
else
seq_force_screen_content_tools = get_bits1(&gb);
if (seq_force_screen_content_tools) {
if (!get_bits1(&gb)) // seq_choose_integer_mv
skip_bits1(&gb); // seq_force_integer_mv
}
if (enable_order_hint)
skip_bits(&gb, 3); // order_hint_bits_minus_1
}
skip_bits(&gb, 3); // enable_superres (1), enable_cdef (1), enable_restoration (1)
parse_color_config(seq_params, &gb);
skip_bits1(&gb); // film_grain_params_present
if (get_bits_left(&gb))
return AVERROR_INVALIDDATA;
return 0;
}
int ff_isom_write_av1c(AVIOContext *pb, const uint8_t *buf, int size)
{
AVIOContext *seq_pb = NULL, *meta_pb = NULL;
AV1SequenceParameters seq_params;
PutBitContext pbc;
uint8_t header[4];
uint8_t *seq = NULL, *meta = NULL;
int64_t obu_size;
int start_pos, type, temporal_id, spatial_id;
int ret, nb_seq = 0, seq_size, meta_size;
if (size <= 0)
return AVERROR_INVALIDDATA;
ret = avio_open_dyn_buf(&seq_pb);
if (ret < 0)
return ret;
ret = avio_open_dyn_buf(&meta_pb);
if (ret < 0)
goto fail;
while (size > 0) {
int len = parse_obu_header(buf, size, &obu_size, &start_pos,
&type, &temporal_id, &spatial_id);
if (len < 0) {
ret = len;
goto fail;
}
switch (type) {
case AV1_OBU_SEQUENCE_HEADER:
nb_seq++;
if (!obu_size || nb_seq > 1) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
ret = parse_sequence_header(&seq_params, buf + start_pos, obu_size);
if (ret < 0)
goto fail;
avio_write(seq_pb, buf, len);
break;
case AV1_OBU_METADATA:
if (!obu_size) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
avio_write(meta_pb, buf, len);
break;
default:
break;
}
size -= len;
buf += len;
}
seq_size = avio_close_dyn_buf(seq_pb, &seq);
if (!seq_size) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
init_put_bits(&pbc, header, sizeof(header));
put_bits(&pbc, 1, 1); // marker
put_bits(&pbc, 7, 1); // version
put_bits(&pbc, 3, seq_params.seq_profile);
put_bits(&pbc, 5, seq_params.seq_level_idx_0);
put_bits(&pbc, 1, seq_params.seq_tier_0);
put_bits(&pbc, 1, seq_params.high_bitdepth);
put_bits(&pbc, 1, seq_params.twelve_bit);
put_bits(&pbc, 1, seq_params.monochrome);
put_bits(&pbc, 1, seq_params.chroma_subsampling_x);
put_bits(&pbc, 1, seq_params.chroma_subsampling_y);
put_bits(&pbc, 2, seq_params.chroma_sample_position);
flush_put_bits(&pbc);
avio_write(pb, header, sizeof(header));
avio_write(pb, seq, seq_size);
meta_size = avio_close_dyn_buf(meta_pb, &meta);
if (meta_size)
avio_write(pb, meta, meta_size);
fail:
if (!seq)
avio_close_dyn_buf(seq_pb, &seq);
if (!meta)
avio_close_dyn_buf(meta_pb, &meta);
av_free(seq);
av_free(meta);
return ret;
}