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LibVideo: Parameterize compound mode parsing in the VP9 decoder

This commit is contained in:
Zaggy1024 2022-11-07 01:34:48 -06:00 committed by Andrew Kaster
parent 372a4ea8c1
commit dd18c42643
3 changed files with 51 additions and 44 deletions

View file

@ -1279,10 +1279,17 @@ DecoderErrorOr<void> Parser::read_ref_frames()
return {};
}
ReferenceMode comp_mode;
if (m_reference_mode == ReferenceModeSelect)
comp_mode = TRY_READ(m_tree_parser->parse_tree<ReferenceMode>(SyntaxElementType::CompMode));
else
if (m_reference_mode == ReferenceModeSelect) {
Optional<bool> above_single = m_available_u ? m_above_single : Optional<bool>();
Optional<bool> left_single = m_available_l ? m_left_single : Optional<bool>();
Optional<bool> above_intra = m_available_u ? m_above_intra : Optional<bool>();
Optional<bool> left_intra = m_available_l ? m_left_intra : Optional<bool>();
Optional<ReferenceFrameType> above_ref_frame_0 = m_available_u ? m_above_ref_frame[0] : Optional<ReferenceFrameType>();
Optional<ReferenceFrameType> left_ref_frame_0 = m_available_l ? m_left_ref_frame[0] : Optional<ReferenceFrameType>();
comp_mode = TRY_READ(TreeParser::parse_comp_mode(*m_bit_stream, *m_probability_tables, *m_syntax_element_counter, m_comp_fixed_ref, above_single, left_single, above_intra, left_intra, above_ref_frame_0, left_ref_frame_0));
} else {
comp_mode = m_reference_mode;
}
if (comp_mode == CompoundReference) {
auto idx = m_ref_frame_sign_bias[m_comp_fixed_ref];
auto comp_ref = TRY_READ(m_tree_parser->parse_tree(SyntaxElementType::CompRef));

View file

@ -306,13 +306,52 @@ ErrorOr<bool> TreeParser::parse_is_inter(BitStream& bit_stream, ProbabilityTable
return value;
}
ErrorOr<ReferenceMode> TreeParser::parse_comp_mode(BitStream& bit_stream, ProbabilityTables const& probability_table, SyntaxElementCounter& counter, ReferenceFrameType comp_fixed_ref, Optional<bool> above_single, Optional<bool> left_single, Optional<bool> above_intra, Optional<bool> left_intra, Optional<ReferenceFrameType> above_ref_frame_0, Optional<ReferenceFrameType> left_ref_frame_0)
{
// FIXME: Above and left contexts should be in structs.
// Probabilities
u8 context;
if (above_single.has_value() && left_single.has_value()) {
if (above_single.value() && left_single.value()) {
auto is_above_fixed = above_ref_frame_0.value() == comp_fixed_ref;
auto is_left_fixed = left_ref_frame_0.value() == comp_fixed_ref;
context = is_above_fixed ^ is_left_fixed;
} else if (above_single.value()) {
auto is_above_fixed = above_ref_frame_0.value() == comp_fixed_ref;
context = 2 + static_cast<u8>(is_above_fixed || above_intra.value());
} else if (left_single.value()) {
auto is_left_fixed = left_ref_frame_0.value() == comp_fixed_ref;
context = 2 + static_cast<u8>(is_left_fixed || left_intra.value());
} else {
context = 4;
}
} else if (above_single.has_value()) {
if (above_single.value())
context = above_ref_frame_0.value() == comp_fixed_ref;
else
context = 3;
} else if (left_single.has_value()) {
if (left_single.value())
context = static_cast<u8>(left_ref_frame_0.value() == comp_fixed_ref);
else
context = 3;
} else {
context = 1;
}
u8 probability = probability_table.comp_mode_prob()[context];
auto value = TRY(parse_tree_new<ReferenceMode>(bit_stream, { binary_tree }, [&](u8) { return probability; }));
increment_counter(counter.m_counts_comp_mode[context][value]);
return value;
}
/*
* Select a tree value based on the type of syntax element being parsed, as well as some parser state, as specified in section 9.3.1
*/
TreeParser::TreeSelection TreeParser::select_tree(SyntaxElementType type)
{
switch (type) {
case SyntaxElementType::CompMode:
case SyntaxElementType::CompRef:
case SyntaxElementType::SingleRefP1:
case SyntaxElementType::SingleRefP2:
@ -347,8 +386,6 @@ TreeParser::TreeSelection TreeParser::select_tree(SyntaxElementType type)
u8 TreeParser::select_tree_probability(SyntaxElementType type, u8 node)
{
switch (type) {
case SyntaxElementType::CompMode:
return calculate_comp_mode_probability();
case SyntaxElementType::CompRef:
return calculate_comp_ref_probability();
case SyntaxElementType::SingleRefP1:
@ -398,40 +435,6 @@ u8 TreeParser::select_tree_probability(SyntaxElementType type, u8 node)
#define ABOVE_SINGLE m_decoder.m_above_single
#define LEFT_SINGLE m_decoder.m_left_single
u8 TreeParser::calculate_comp_mode_probability()
{
if (AVAIL_U && AVAIL_L) {
if (ABOVE_SINGLE && LEFT_SINGLE) {
auto is_above_fixed = ABOVE_FRAME_0 == m_decoder.m_comp_fixed_ref;
auto is_left_fixed = LEFT_FRAME_0 == m_decoder.m_comp_fixed_ref;
m_ctx = is_above_fixed ^ is_left_fixed;
} else if (ABOVE_SINGLE) {
auto is_above_fixed = ABOVE_FRAME_0 == m_decoder.m_comp_fixed_ref;
m_ctx = 2 + (is_above_fixed || ABOVE_INTRA);
} else if (LEFT_SINGLE) {
auto is_left_fixed = LEFT_FRAME_0 == m_decoder.m_comp_fixed_ref;
m_ctx = 2 + (is_left_fixed || LEFT_INTRA);
} else {
m_ctx = 4;
}
} else if (AVAIL_U) {
if (ABOVE_SINGLE) {
m_ctx = ABOVE_FRAME_0 == m_decoder.m_comp_fixed_ref;
} else {
m_ctx = 3;
}
} else if (AVAIL_L) {
if (LEFT_SINGLE) {
m_ctx = LEFT_FRAME_0 == m_decoder.m_comp_fixed_ref;
} else {
m_ctx = 3;
}
} else {
m_ctx = 1;
}
return m_decoder.m_probability_tables->comp_mode_prob()[m_ctx];
}
u8 TreeParser::calculate_comp_ref_probability()
{
auto fix_ref_idx = m_decoder.m_ref_frame_sign_bias[m_decoder.m_comp_fixed_ref];
@ -722,9 +725,6 @@ void TreeParser::count_syntax_element(SyntaxElementType type, int value)
increment_counter(count);
};
switch (type) {
case SyntaxElementType::CompMode:
increment(m_decoder.m_syntax_element_counter->m_counts_comp_mode[m_ctx][value]);
return;
case SyntaxElementType::CompRef:
increment(m_decoder.m_syntax_element_counter->m_counts_comp_ref[m_ctx][value]);
return;

View file

@ -75,6 +75,7 @@ public:
static ErrorOr<bool> parse_skip(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, Optional<bool> const& above_skip, Optional<bool> const& left_skip);
static ErrorOr<TXSize> parse_tx_size(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, TXSize max_tx_size, Optional<bool> above_skip, Optional<bool> left_skip, Optional<TXSize> above_tx_size, Optional<TXSize> left_tx_size);
static ErrorOr<bool> parse_is_inter(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, Optional<bool> above_intra, Optional<bool> left_intra);
static ErrorOr<ReferenceMode> parse_comp_mode(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, ReferenceFrameType comp_fixed_ref, Optional<bool> above_single, Optional<bool> left_single, Optional<bool> above_intra, Optional<bool> left_intra, Optional<ReferenceFrameType> above_ref_frame_0, Optional<ReferenceFrameType> left_ref_frame_0);
void set_default_intra_mode_variables(u8 idx, u8 idy)
{
@ -108,7 +109,6 @@ public:
}
private:
u8 calculate_comp_mode_probability();
u8 calculate_comp_ref_probability();
u8 calculate_single_ref_p1_probability();
u8 calculate_single_ref_p2_probability();