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LibVideo/VP9: Begin creating a tree parser to parse syntax elements

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This commit is contained in:
FalseHonesty 2021-01-30 15:18:59 -05:00 • committed by Andreas Kling
parent cfd65eafa9
commit 7ff6315246
7 changed files with 457 additions and 20 deletions
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33
Userland/Libraries/LibVideo/VP9/Decoder.cpp
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@ -13,14 +13,16 @@ namespace Video::VP9 {
return false
Decoder::Decoder()
: m_probability_tables(make<ProbabilityTables>())
, m_tree_parser(make<TreeParser>(*m_probability_tables))
{
m_probability_tables = make<ProbabilityTables>();
}
bool Decoder::parse_frame(const ByteBuffer& frame_data)
{
m_bit_stream = make<BitStream>(frame_data.data(), frame_data.size());
m_syntax_element_counter = make<SyntaxElementCounter>();
m_tree_parser->set_bit_stream(m_bit_stream);
if (!uncompressed_header())
return false;
@ -126,6 +128,8 @@ bool Decoder::uncompressed_header()
}
}
m_tree_parser->set_frame_is_intra(m_frame_is_intra);
if (!m_error_resilient_mode) {
m_refresh_frame_context = m_bit_stream->read_bit();
m_frame_parallel_decoding_mode = m_bit_stream->read_bit();
@ -440,10 +444,10 @@ bool Decoder::compressed_header()
bool Decoder::read_tx_mode()
{
if (m_lossless) {
m_tx_mode = Only4x4;
m_tx_mode = Only_4x4;
} else {
auto tx_mode = m_bit_stream->read_literal(2);
if (tx_mode == Allow32x32) {
if (tx_mode == Allow_32x32) {
tx_mode += m_bit_stream->read_literal(1);
}
m_tx_mode = static_cast<TXMode>(tx_mode);
@ -456,17 +460,17 @@ bool Decoder::tx_mode_probs()
auto& tx_probs = m_probability_tables->tx_probs();
for (auto i = 0; i < TX_SIZE_CONTEXTS; i++) {
for (auto j = 0; j < TX_SIZES - 3; j++) {
tx_probs[TX8x8][i][j] = diff_update_prob(tx_probs[TX8x8][i][j]);
tx_probs[TX_8x8][i][j] = diff_update_prob(tx_probs[TX_8x8][i][j]);
}
}
for (auto i = 0; i < TX_SIZE_CONTEXTS; i++) {
for (auto j = 0; j < TX_SIZES - 2; j++) {
tx_probs[TX16x16][i][j] = diff_update_prob(tx_probs[TX16x16][i][j]);
tx_probs[TX_16x16][i][j] = diff_update_prob(tx_probs[TX_16x16][i][j]);
}
}
for (auto i = 0; i < TX_SIZE_CONTEXTS; i++) {
for (auto j = 0; j < TX_SIZES - 1; j++) {
tx_probs[TX32x32][i][j] = diff_update_prob(tx_probs[TX32x32][i][j]);
tx_probs[TX_32x32][i][j] = diff_update_prob(tx_probs[TX_32x32][i][j]);
}
}
return true;
@ -517,7 +521,8 @@ u8 Decoder::inv_recenter_nonneg(u8 v, u8 m)
bool Decoder::read_coef_probs()
{
auto max_tx_size = tx_mode_to_biggest_tx_size[m_tx_mode];
for (auto tx_size = TX4x4; tx_size <= max_tx_size; tx_size = static_cast<TXSize>(static_cast<int>(tx_size) + 1)) {
m_tree_parser->set_max_tx_size(max_tx_size);
for (auto tx_size = TX_4x4; tx_size <= max_tx_size; tx_size = static_cast<TXSize>(static_cast<int>(tx_size) + 1)) {
auto update_probs = m_bit_stream->read_literal(1);
if (update_probs == 1) {
for (auto i = 0; i < 2; i++) {
@ -760,7 +765,9 @@ bool Decoder::decode_tile()
for (auto row = m_mi_row_start; row < m_mi_row_end; row += 8) {
if (!clear_left_context())
return false;
m_tree_parser->set_row(row);
for (auto col = m_mi_col_start; col < m_mi_col_end; col += 8) {
m_tree_parser->set_col(col);
if (!decode_partition(row, col, Block_64x64))
return false;
}
@ -787,9 +794,15 @@ bool Decoder::decode_partition(u32 row, u32 col, u8 block_subsize)
auto has_rows = (row + half_block_8x8) < m_mi_rows;
auto has_cols = (col + half_block_8x8) < m_mi_cols;
// FIXME: Parse partition (type: T) as specified by spec in section 9.3
(void)has_rows;
(void)has_cols;
m_tree_parser->set_has_rows(has_rows);
m_tree_parser->set_has_cols(has_cols);
m_tree_parser->set_block_subsize(block_subsize);
m_tree_parser->set_num_8x8(num_8x8);
auto partition = m_tree_parser->parse_tree(SyntaxElementType::Partition);
dbgln("Parsed partition value {}", partition);
// FIXME: Finish implementing partition decoding
return true;
}