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LibGfx: Remove some of the noisier logging from webp lossless decoder

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Prefix code decoding seems to work fairly well and produces a ton of
log output with `#define WEBP_DEBUG 1`, so remove the log lines.

(If needed it's always possible to just locally revert this commit.)

No behavior change, since WEBP_DEBUG isn't usually defined.
This commit is contained in:
Nico Weber 2023-04-09 10:09:21 -04:00 • committed by Linus Groh
parent 4107ae1dea
commit bed86fb578
1 changed files with 1 additions and 8 deletions
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9
Userland/Libraries/LibGfx/ImageFormats/WebPLoader.cpp
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@ -414,10 +414,8 @@ static ErrorOr<CanonicalCode> decode_webp_chunk_VP8L_prefix_code(WebPLoadingCont
constexpr int kCodeLengthCodes = 19;
int kCodeLengthCodeOrder[kCodeLengthCodes] = { 17, 18, 0, 1, 2, 3, 4, 5, 16, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 };
u8 code_length_code_lengths[kCodeLengthCodes] = { 0 }; // "All zeros" [sic]
for (int i = 0; i < num_code_lengths; ++i) {
for (int i = 0; i < num_code_lengths; ++i)
code_length_code_lengths[kCodeLengthCodeOrder[i]] = TRY(bit_stream.read_bits(3));
dbgln_if(WEBP_DEBUG, " code_length_code_lengths[{}] = {}", kCodeLengthCodeOrder[i], code_length_code_lengths[kCodeLengthCodeOrder[i]]);
}
// The spec is at best misleading here, suggesting that max_symbol should be set to "num_code_lengths" if it's not explicitly stored.
// But num_code_lengths doesn't mean the num_code_lengths mentioned a few lines further up in the spec (and in scope here),
@ -452,14 +450,12 @@ static ErrorOr<CanonicalCode> decode_webp_chunk_VP8L_prefix_code(WebPLoadingCont
if (symbol < 16) {
// "Code [0..15] indicates literal code lengths."
dbgln_if(WEBP_DEBUG, " append {}", symbol);
code_lengths.append(static_cast<u8>(symbol));
if (symbol != 0)
last_non_zero = symbol;
} else if (symbol == 16) {
// "Code 16 repeats the previous non-zero value [3..6] times, i.e., 3 + ReadBits(2) times."
auto nrepeat = 3 + TRY(bit_stream.read_bits(2));
dbgln_if(WEBP_DEBUG, " repeat {} {}s", nrepeat, last_non_zero);
// This is different from deflate.
for (size_t j = 0; j < nrepeat; ++j)
@ -467,14 +463,12 @@ static ErrorOr<CanonicalCode> decode_webp_chunk_VP8L_prefix_code(WebPLoadingCont
} else if (symbol == 17) {
// "Code 17 emits a streak of zeros [3..10], i.e., 3 + ReadBits(3) times."
auto nrepeat = 3 + TRY(bit_stream.read_bits(3));
dbgln_if(WEBP_DEBUG, " repeat {} zeroes", nrepeat);
for (size_t j = 0; j < nrepeat; ++j)
code_lengths.append(0);
} else {
VERIFY(symbol == 18);
// "Code 18 emits a streak of zeros of length [11..138], i.e., 11 + ReadBits(7) times."
auto nrepeat = 11 + TRY(bit_stream.read_bits(7));
dbgln_if(WEBP_DEBUG, " Repeat {} zeroes", nrepeat);
for (size_t j = 0; j < nrepeat; ++j)
code_lengths.append(0);
}
@ -483,7 +477,6 @@ static ErrorOr<CanonicalCode> decode_webp_chunk_VP8L_prefix_code(WebPLoadingCont
if (code_lengths.size() > alphabet_size)
return Error::from_string_literal("Number of code lengths is larger than the alphabet size");
dbgln_if(WEBP_DEBUG, " done reading symbols");
return CanonicalCode::from_bytes(code_lengths);
}