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LibVideo/VP9: Implement lossless residual decoding

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Zaggy1024 2023-07-06 13:22:01 -05:00 committed by Tim Flynn
parent 2a4f2110b9
commit 888af08638
Notes: sideshowbarker 2024-07-17 02:38:39 +09:00 
Author: https://github.com/Zaggy1024
Commit: https://github.com/SerenityOS/serenity/commit/888af08638
Pull-request: https://github.com/SerenityOS/serenity/pull/19851
1 changed files with 53 additions and 40 deletions
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93
Userland/Libraries/LibVideo/VP9/Decoder.cpp
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@ -1292,14 +1292,27 @@ DecoderErrorOr<void> Decoder::reconstruct_templated(u8 plane, BlockContext const
inline DecoderErrorOr<void> Decoder::inverse_walsh_hadamard_transform(Span<Intermediate> data, u8 log2_of_block_size, u8 shift) inline DecoderErrorOr<void> Decoder::inverse_walsh_hadamard_transform(Span<Intermediate> data, u8 log2_of_block_size, u8 shift)
{ {
(void)data;
(void)shift;
// The input to this process is a variable shift that specifies the amount of pre-scaling. // The input to this process is a variable shift that specifies the amount of pre-scaling.
// This process does an in-place transform of the array T (of length 4) by the following ordered steps: // This process does an in-place transform of the array T (of length 4) by the following ordered steps:
if (1 << log2_of_block_size != 4) if (1 << log2_of_block_size != 4)
return DecoderError::corrupted("Block size was not 4"sv); return DecoderError::corrupted("Block size was not 4"sv);
return DecoderError::not_implemented(); auto a = data[0] >> shift;
auto c = data[1] >> shift;
auto d = data[2] >> shift;
auto b = data[3] >> shift;
a += c;
d -= b;
auto average_of_a_and_d = (a - d) >> 1;
b = average_of_a_and_d - b;
c = average_of_a_and_d - c;
a -= b;
d += c;
data[0] = a;
data[1] = b;
data[2] = c;
data[3] = d;
return {};
} }
inline i32 Decoder::cos64(u8 angle) inline i32 Decoder::cos64(u8 angle)
@ -1817,24 +1830,24 @@ ALWAYS_INLINE DecoderErrorOr<void> Decoder::inverse_transform_2d(BlockContext co
// to 2. // to 2.
if (block_context.frame_context.lossless) { if (block_context.frame_context.lossless) {
TRY(inverse_walsh_hadamard_transform(row, log2_of_block_size, 2)); TRY(inverse_walsh_hadamard_transform(row, log2_of_block_size, 2));
continue; } else {
} switch (transform_set.second_transform) {
switch (transform_set.second_transform) { case TransformType::DCT:
case TransformType::DCT: // Otherwise, if TxType is equal to DCT_DCT or TxType is equal to ADST_DCT, apply an inverse DCT as
// Otherwise, if TxType is equal to DCT_DCT or TxType is equal to ADST_DCT, apply an inverse DCT as // follows:
// follows: // 1. Invoke the inverse DCT permutation process as specified in section 8.7.1.2 with the input variable n.
// 1. Invoke the inverse DCT permutation process as specified in section 8.7.1.2 with the input variable n. TRY(inverse_discrete_cosine_transform_array_permutation<log2_of_block_size>(row));
TRY(inverse_discrete_cosine_transform_array_permutation<log2_of_block_size>(row)); // 2. Invoke the inverse DCT process as specified in section 8.7.1.3 with the input variable n.
// 2. Invoke the inverse DCT process as specified in section 8.7.1.3 with the input variable n. TRY(inverse_discrete_cosine_transform<log2_of_block_size>(row));
TRY(inverse_discrete_cosine_transform<log2_of_block_size>(row)); break;
break; case TransformType::ADST:
case TransformType::ADST: // 4. Otherwise (TxType is equal to DCT_ADST or TxType is equal to ADST_ADST), invoke the inverse ADST
// 4. Otherwise (TxType is equal to DCT_ADST or TxType is equal to ADST_ADST), invoke the inverse ADST // process as specified in section 8.7.1.9 with input variable n.
// process as specified in section 8.7.1.9 with input variable n. TRY(inverse_asymmetric_discrete_sine_transform<log2_of_block_size>(row));
TRY(inverse_asymmetric_discrete_sine_transform<log2_of_block_size>(row)); break;
break; default:
default: return DecoderError::corrupted("Unknown tx_type"sv);
return DecoderError::corrupted("Unknown tx_type"sv); }
} }
// 5. Set Dequant[ i ][ j ] equal to T[ j ] for j = 0..(n0-1). // 5. Set Dequant[ i ][ j ] equal to T[ j ] for j = 0..(n0-1).
@ -1854,25 +1867,25 @@ ALWAYS_INLINE DecoderErrorOr<void> Decoder::inverse_transform_2d(BlockContext co
// 2. If Lossless is equal to 1, invoke the Inverse WHT process as specified in section 8.7.1.10 with shift equal // 2. If Lossless is equal to 1, invoke the Inverse WHT process as specified in section 8.7.1.10 with shift equal
// to 0. // to 0.
if (block_context.frame_context.lossless) { if (block_context.frame_context.lossless) {
TRY(inverse_walsh_hadamard_transform(column, log2_of_block_size, 2)); TRY(inverse_walsh_hadamard_transform(column, log2_of_block_size, 0));
continue; } else {
} switch (transform_set.first_transform) {
switch (transform_set.first_transform) { case TransformType::DCT:
case TransformType::DCT: // Otherwise, if TxType is equal to DCT_DCT or TxType is equal to DCT_ADST, apply an inverse DCT as
// Otherwise, if TxType is equal to DCT_DCT or TxType is equal to DCT_ADST, apply an inverse DCT as // follows:
// follows: // 1. Invoke the inverse DCT permutation process as specified in section 8.7.1.2 with the input variable n.
// 1. Invoke the inverse DCT permutation process as specified in section 8.7.1.2 with the input variable n. TRY(inverse_discrete_cosine_transform_array_permutation<log2_of_block_size>(column));
TRY(inverse_discrete_cosine_transform_array_permutation<log2_of_block_size>(column)); // 2. Invoke the inverse DCT process as specified in section 8.7.1.3 with the input variable n.
// 2. Invoke the inverse DCT process as specified in section 8.7.1.3 with the input variable n. TRY(inverse_discrete_cosine_transform<log2_of_block_size>(column));
TRY(inverse_discrete_cosine_transform<log2_of_block_size>(column)); break;
break; case TransformType::ADST:
case TransformType::ADST: // 4. Otherwise (TxType is equal to ADST_DCT or TxType is equal to ADST_ADST), invoke the inverse ADST
// 4. Otherwise (TxType is equal to ADST_DCT or TxType is equal to ADST_ADST), invoke the inverse ADST // process as specified in section 8.7.1.9 with input variable n.
// process as specified in section 8.7.1.9 with input variable n. TRY(inverse_asymmetric_discrete_sine_transform<log2_of_block_size>(column));
TRY(inverse_asymmetric_discrete_sine_transform<log2_of_block_size>(column)); break;
break; default:
default: VERIFY_NOT_REACHED();
VERIFY_NOT_REACHED(); }
} }
// 5. If Lossless is equal to 1, set Dequant[ i ][ j ] equal to T[ i ] for i = 0..(n0-1). // 5. If Lossless is equal to 1, set Dequant[ i ][ j ] equal to T[ i ] for i = 0..(n0-1).