LibGfx+LibPDF: Use LibCompress' implementation of the PackBits decoder

No need to have these three copies :^)
This commit is contained in:
Lucas CHOLLET 2023-12-21 00:17:37 -05:00 committed by Tim Schumacher
parent d748edd994
commit f389c1cdba
Notes: sideshowbarker 2024-07-16 22:24:48 +09:00
3 changed files with 7 additions and 95 deletions

View file

@ -9,6 +9,7 @@
#include <AK/Endian.h>
#include <AK/FixedArray.h>
#include <AK/IntegralMath.h>
#include <LibCompress/PackBitsDecoder.h>
#include <LibGfx/FourCC.h>
#include <LibGfx/ImageFormats/ILBMLoader.h>
@ -246,39 +247,7 @@ static ErrorOr<ByteBuffer> uncompress_byte_run(ReadonlyBytes data, ILBMLoadingCo
if (plane_data_size > NumericLimits<u32>::max() || ceil_div(plane_data_size, 127ul) > length)
return Error::from_string_literal("Uncompressed data size too large");
auto plane_data = TRY(ByteBuffer::create_uninitialized(plane_data_size));
u32 index = 0;
u32 read_bytes = 0;
// Uncompressing is done once we've read all buffer or plane buffer has been fully filled
while (read_bytes < length && index < plane_data_size) {
auto const byte = static_cast<i8>(data[read_bytes++]);
if (byte >= -127 && byte <= -1) {
// read next byte
if (read_bytes == data.size())
return Error::from_string_literal("Malformed compressed data");
u8 next_byte = data[read_bytes++];
if (index + -byte >= plane_data.size())
return Error::from_string_literal("Malformed compressed data");
for (u16 i = 0; i < -byte + 1; ++i) {
plane_data[index++] = next_byte;
}
} else if (byte >= 0) {
if (index + byte >= plane_data_size || read_bytes + byte >= length)
return Error::from_string_literal("Malformed compressed data");
for (u16 i = 0; i < byte + 1; ++i) {
plane_data[index] = data[read_bytes];
read_bytes++;
index++;
}
}
}
if (index != plane_data_size)
return Error::from_string_literal("Unexpected end of chunk while decompressing data");
auto plane_data = TRY(Compress::PackBits::decode_all(data, plane_data_size));
return plane_data;
}

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@ -9,6 +9,7 @@
#include <AK/Endian.h>
#include <AK/String.h>
#include <LibCompress/LZWDecoder.h>
#include <LibCompress/PackBitsDecoder.h>
#include <LibGfx/ImageFormats/CCITTDecoder.h>
#include <LibGfx/ImageFormats/TIFFMetadata.h>
@ -284,44 +285,8 @@ private:
ByteBuffer decoded_bytes {};
auto decode_packbits_strip = [&](u32 num_bytes) -> ErrorOr<ReadonlyBytes> {
auto strip_stream = make<FixedMemoryStream>(TRY(m_stream->read_in_place<u8 const>(num_bytes)));
decoded_bytes.clear();
Optional<i8> n {};
Optional<u8> saved_byte {};
while (strip_stream->remaining() > 0 || saved_byte.has_value()) {
if (!n.has_value())
n = TRY(strip_stream->read_value<i8>());
if (n.value() >= 0 && !saved_byte.has_value()) {
n.value() = n.value() - 1;
if (n.value() == -1)
n.clear();
decoded_bytes.append(TRY(strip_stream->read_value<u8>()));
continue;
}
if (n.value() == -128) {
n.clear();
continue;
}
if (!saved_byte.has_value())
saved_byte = TRY(strip_stream->read_value<u8>());
n.value() = n.value() + 1;
decoded_bytes.append(*saved_byte);
if (n == 1) {
saved_byte.clear();
n.clear();
}
}
auto const encoded_bytes = TRY(m_stream->read_in_place<u8 const>(num_bytes));
decoded_bytes = TRY(Compress::PackBits::decode_all(encoded_bytes));
return decoded_bytes;
};

View file

@ -8,6 +8,7 @@
#include <AK/Hex.h>
#include <LibCompress/Deflate.h>
#include <LibCompress/LZWDecoder.h>
#include <LibCompress/PackBitsDecoder.h>
#include <LibGfx/ImageFormats/JPEGLoader.h>
#include <LibGfx/ImageFormats/PNGLoader.h>
#include <LibPDF/CommonNames.h>
@ -210,30 +211,7 @@ PDFErrorOr<ByteBuffer> Filter::decode_flate(ReadonlyBytes bytes, int predictor,
PDFErrorOr<ByteBuffer> Filter::decode_run_length(ReadonlyBytes bytes)
{
constexpr size_t END_OF_DECODING = 128;
ByteBuffer buffer {};
while (true) {
VERIFY(bytes.size() > 0);
auto length = bytes[0];
bytes = bytes.slice(1);
if (length == END_OF_DECODING) {
VERIFY(bytes.is_empty());
break;
}
if (length < 128) {
TRY(buffer.try_append(bytes.slice(0, length + 1)));
bytes = bytes.slice(length + 1);
} else {
VERIFY(bytes.size() > 1);
auto byte_to_append = bytes[0];
bytes = bytes.slice(1);
size_t n_chars = 257 - length;
for (size_t i = 0; i < n_chars; ++i) {
TRY(buffer.try_append(byte_to_append));
}
}
}
return buffer;
return TRY(Compress::PackBits::decode_all(bytes, OptionalNone {}, Compress::PackBits::CompatibilityMode::PDF));
}
PDFErrorOr<ByteBuffer> Filter::decode_ccitt(ReadonlyBytes)