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LibVideo: Parameterize interpolation filter parsing for the VP9 decoder

This commit is contained in:
Zaggy1024 2022-11-06 20:44:45 -06:00 committed by Andrew Kaster
parent cbb8a3f0f4
commit 568e2fc1f2
3 changed files with 38 additions and 33 deletions

View file

@ -1219,10 +1219,15 @@ DecoderErrorOr<void> Parser::inter_block_mode_info()
} else if (m_mi_size >= Block_8x8) {
m_y_mode = TRY_READ(TreeParser::parse_inter_mode(*m_bit_stream, *m_probability_tables, *m_syntax_element_counter, m_mode_context[m_ref_frame[0]]));
}
if (m_interpolation_filter == Switchable)
m_interp_filter = TRY_READ(m_tree_parser->parse_tree<InterpolationFilter>(SyntaxElementType::InterpFilter));
else
if (m_interpolation_filter == Switchable) {
Optional<ReferenceFrameType> above_ref_frame = m_available_u ? m_ref_frames[get_image_index(m_mi_row - 1, m_mi_col)][0] : Optional<ReferenceFrameType>();
Optional<ReferenceFrameType> left_ref_frame = m_available_l ? m_ref_frames[get_image_index(m_mi_row, m_mi_col - 1)][0] : Optional<ReferenceFrameType>();
Optional<InterpolationFilter> above_interpolation_filter = m_available_u ? m_interp_filters[get_image_index(m_mi_row - 1, m_mi_col)] : Optional<InterpolationFilter>();
Optional<InterpolationFilter> left_interpolation_filter = m_available_l ? m_interp_filters[get_image_index(m_mi_row, m_mi_col - 1)] : Optional<InterpolationFilter>();
m_interp_filter = TRY_READ(TreeParser::parse_interpolation_filter(*m_bit_stream, *m_probability_tables, *m_syntax_element_counter, above_ref_frame, left_ref_frame, above_interpolation_filter, left_interpolation_filter));
} else {
m_interp_filter = m_interpolation_filter;
}
if (m_mi_size < Block_8x8) {
m_num_4x4_w = num_4x4_blocks_wide_lookup[m_mi_size];
m_num_4x4_h = num_4x4_blocks_high_lookup[m_mi_size];

View file

@ -200,6 +200,35 @@ ErrorOr<PredictionMode> TreeParser::parse_inter_mode(BitStream& bit_stream, Prob
return value;
}
ErrorOr<InterpolationFilter> TreeParser::parse_interpolation_filter(BitStream& bit_stream, ProbabilityTables const& probability_table, SyntaxElementCounter& counter, Optional<ReferenceFrameType> above_ref_frame, Optional<ReferenceFrameType> left_ref_frame, Optional<InterpolationFilter> above_interpolation_filter, Optional<InterpolationFilter> left_interpolation_filter)
{
// FIXME: Above and left context should be provided by a struct.
// Tree
TreeParser::TreeSelection tree = { interp_filter_tree };
// Probabilities
// NOTE: SWITCHABLE_FILTERS is not used in the spec for this function. Therefore, the number
// was demystified by referencing the reference codec libvpx:
// https://github.com/webmproject/libvpx/blob/705bf9de8c96cfe5301451f1d7e5c90a41c64e5f/vp9/common/vp9_pred_common.h#L69
u8 left_interp = (left_ref_frame.has_value() && left_ref_frame.value() > IntraFrame)
? left_interpolation_filter.value()
: SWITCHABLE_FILTERS;
u8 above_interp = (above_ref_frame.has_value() && above_ref_frame.value() > IntraFrame)
? above_interpolation_filter.value()
: SWITCHABLE_FILTERS;
u8 context = SWITCHABLE_FILTERS;
if (above_interp == left_interp || above_interp == SWITCHABLE_FILTERS)
context = left_interp;
else if (left_interp == SWITCHABLE_FILTERS)
context = above_interp;
u8 const* probabilities = probability_table.interp_filter_probs()[context];
auto value = TRY(parse_tree_new<InterpolationFilter>(bit_stream, tree, [&](u8 node) { return probabilities[node]; }));
increment_counter(counter.m_counts_interp_filter[context][to_underlying(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
*/
@ -226,8 +255,6 @@ TreeParser::TreeSelection TreeParser::select_tree(SyntaxElementType type)
if (m_decoder.m_max_tx_size == TX_16x16)
return { tx_size_16_tree };
return { tx_size_8_tree };
case SyntaxElementType::InterpFilter:
return { interp_filter_tree };
case SyntaxElementType::MVJoint:
return { mv_joint_tree };
case SyntaxElementType::MVClass:
@ -279,8 +306,6 @@ u8 TreeParser::select_tree_probability(SyntaxElementType type, u8 node)
return m_decoder.m_probability_tables->mv_bits_prob()[m_mv_component][m_mv_bit];
case SyntaxElementType::TXSize:
return calculate_tx_size_probability(node);
case SyntaxElementType::InterpFilter:
return calculate_interp_filter_probability(node);
case SyntaxElementType::MVJoint:
return m_decoder.m_probability_tables->mv_joint_probs()[node];
case SyntaxElementType::MVClass:
@ -619,28 +644,6 @@ u8 TreeParser::calculate_tx_size_probability(u8 node)
return m_decoder.m_probability_tables->tx_probs()[m_decoder.m_max_tx_size][m_ctx][node];
}
u8 TreeParser::calculate_interp_filter_probability(u8 node)
{
// NOTE: SWITCHABLE_FILTERS is not used in the spec for this function. Therefore, the number
// was demystified by referencing the reference codec libvpx:
// https://github.com/webmproject/libvpx/blob/705bf9de8c96cfe5301451f1d7e5c90a41c64e5f/vp9/common/vp9_pred_common.h#L69
auto left_interp = (AVAIL_L && m_decoder.m_left_ref_frame[0] > IntraFrame)
? m_decoder.m_interp_filters[m_decoder.get_image_index(m_decoder.m_mi_row, m_decoder.m_mi_col - 1)]
: SWITCHABLE_FILTERS;
auto above_interp = (AVAIL_U && m_decoder.m_above_ref_frame[0] > IntraFrame)
? m_decoder.m_interp_filters[m_decoder.get_image_index(m_decoder.m_mi_row - 1, m_decoder.m_mi_col)]
: SWITCHABLE_FILTERS;
if (left_interp == above_interp)
m_ctx = left_interp;
else if (left_interp == SWITCHABLE_FILTERS)
m_ctx = above_interp;
else if (above_interp == SWITCHABLE_FILTERS)
m_ctx = left_interp;
else
m_ctx = SWITCHABLE_FILTERS;
return m_decoder.m_probability_tables->interp_filter_probs()[m_ctx][node];
}
void TreeParser::set_tokens_variables(u8 band, u32 c, u32 plane, TXSize tx_size, u32 pos)
{
m_band = band;
@ -750,9 +753,6 @@ void TreeParser::count_syntax_element(SyntaxElementType type, int value)
case SyntaxElementType::TXSize:
increment(m_decoder.m_syntax_element_counter->m_counts_tx_size[m_decoder.m_max_tx_size][m_ctx][value]);
return;
case SyntaxElementType::InterpFilter:
increment(m_decoder.m_syntax_element_counter->m_counts_interp_filter[m_ctx][value]);
return;
case SyntaxElementType::MVJoint:
increment(m_decoder.m_syntax_element_counter->m_counts_mv_joint[value]);
return;

View file

@ -69,6 +69,7 @@ public:
static ErrorOr<PredictionMode> parse_sub_intra_mode(BitStream&, ProbabilityTables const&, SyntaxElementCounter&);
static ErrorOr<PredictionMode> parse_uv_mode(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, PredictionMode y_mode);
static ErrorOr<PredictionMode> parse_inter_mode(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, u8 mode_context_for_ref_frame_0);
static ErrorOr<InterpolationFilter> parse_interpolation_filter(BitStream&, ProbabilityTables const&, SyntaxElementCounter&, Optional<ReferenceFrameType> above_ref_frame, Optional<ReferenceFrameType> left_ref_frame, Optional<InterpolationFilter> above_interpolation_filter, Optional<InterpolationFilter> left_interpolation_filter);
void set_default_intra_mode_variables(u8 idx, u8 idy)
{
@ -111,7 +112,6 @@ private:
u8 calculate_single_ref_p1_probability();
u8 calculate_single_ref_p2_probability();
u8 calculate_tx_size_probability(u8 node);
u8 calculate_interp_filter_probability(u8 node);
u8 calculate_token_probability(u8 node);
u8 calculate_more_coefs_probability();