LibImage: Start work on PNG decoding
This patch adds PNG decoder that currently only inflates the PNG's zlib deflate stream
This commit is contained in:
parent
aaf7a249c6
commit
65c6d62a15
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@ -5,6 +5,7 @@ project(libimage CXX)
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set(LIBIMAGE_SOURCES
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Image.cpp
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Netbpm.cpp
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PNG.cpp
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)
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add_custom_target(libimage-headers
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@ -3,6 +3,7 @@
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#include <LibImage/Image.h>
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#include <LibImage/Netbpm.h>
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#include <LibImage/PNG.h>
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#include <fcntl.h>
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#include <stdlib.h>
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@ -55,6 +56,9 @@ namespace LibImage
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if (probe_netbpm(image_data_span))
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return TRY(load_netbpm(image_data_span));
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if (probe_png(image_data_span))
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return TRY(load_png(image_data_span));
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fprintf(stderr, "unrecognized image format\n");
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return BAN::Error::from_errno(ENOTSUP);
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}
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@ -0,0 +1,668 @@
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#include <BAN/Debug.h>
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#include <BAN/Endianness.h>
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#include <LibImage/PNG.h>
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#include <ctype.h>
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namespace LibImage
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{
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template<BAN::integral T>
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struct PODNetworkEndian
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{
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T raw;
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constexpr operator T() const { return BAN::network_endian_to_host(raw); }
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};
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enum class ColourType : uint8_t
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{
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Greyscale = 0,
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Truecolour = 2,
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IndexedColour = 3,
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GreyscaleAlpha = 4,
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TruecolourAlpha = 6,
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};
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enum class CompressionMethod : uint8_t
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{
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Deflate = 0,
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};
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enum class FilterMethod : uint8_t
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{
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Adaptive = 0,
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};
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enum class InterlaceMethod : uint8_t
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{
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NoInterlace = 0,
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Adam7 = 1,
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};
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struct IHDR
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{
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PODNetworkEndian<uint32_t> width;
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PODNetworkEndian<uint32_t> height;
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uint8_t bit_depth;
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ColourType colour_type;
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CompressionMethod compression_method;
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FilterMethod filter_method;
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InterlaceMethod interlace_method;
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} __attribute__((packed));
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struct PaletteEntry
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{
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uint8_t red;
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uint8_t green;
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uint8_t blue;
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};
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struct ZLibStream
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{
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uint8_t cm : 4;
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uint8_t cinfo : 4;
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uint8_t fcheck : 5;
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uint8_t fdict : 1;
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uint8_t flevel : 2;
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};
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struct PNGChunk
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{
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BAN::StringView name;
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BAN::ConstByteSpan data;
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};
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class BinaryBuffer
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{
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public:
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BinaryBuffer(BAN::Vector<BAN::ConstByteSpan> data)
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: m_data(data)
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{}
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BAN::ErrorOr<uint16_t> peek_bits(uint8_t count)
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{
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ASSERT(count <= 16);
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while (m_bit_buffer_len < count)
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{
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if (m_data.empty())
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return BAN::Error::from_errno(ENODATA);
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m_bit_buffer |= m_data[0][0] << m_bit_buffer_len;
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m_bit_buffer_len += 8;
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if (m_data[0].size() > 1)
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m_data[0] = m_data[0].slice(1);
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else
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m_data.remove(0);
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}
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return m_bit_buffer & ((1 << count) - 1);
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}
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void remove_bits(uint8_t count)
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{
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ASSERT(count <= 16);
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ASSERT(m_bit_buffer_len >= count);
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m_bit_buffer_len -= count;
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m_bit_buffer >>= count;
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}
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BAN::ErrorOr<uint16_t> get_bits(uint8_t count)
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{
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uint16_t result = TRY(peek_bits(count));
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remove_bits(count);
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return result;
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}
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void skip_to_byte_boundary()
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{
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m_bit_buffer >>= m_bit_buffer_len % 8;
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m_bit_buffer_len -= m_bit_buffer_len % 8;
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}
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private:
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BAN::Vector<BAN::ConstByteSpan> m_data;
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uint32_t m_bit_buffer { 0 };
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uint8_t m_bit_buffer_len { 0 };
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};
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constexpr uint16_t reverse_bits(uint16_t value, uint8_t count)
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{
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uint16_t reverse = 0;
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for (uint8_t bit = 0; bit < count; bit++)
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reverse |= ((value >> bit) & 1) << (count - bit - 1);
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return reverse;
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}
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// https://www.rfc-editor.org/rfc/rfc1951
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class HuffmanTree
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{
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public:
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static constexpr uint8_t MAX_BITS = 15;
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struct Leaf
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{
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uint16_t code;
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uint8_t len;
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};
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public:
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HuffmanTree() = default;
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HuffmanTree(BAN::Vector<Leaf>&& leaves, uint8_t min_len, uint8_t max_len, uint8_t instant_max_bit)
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: m_leaves(BAN::move(leaves))
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, m_min_bits(min_len), m_max_bits(max_len)
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, m_instant_max_bit(instant_max_bit)
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{}
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uint8_t min_bits() const { return m_min_bits; }
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uint8_t max_bits() const { return m_max_bits; }
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uint8_t instant_max_bit() const { return m_instant_max_bit; }
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Leaf get_leaf(size_t index) const { return m_leaves[index]; }
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bool empty() const { return m_leaves.empty(); }
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static BAN::ErrorOr<HuffmanTree> create(const BAN::Vector<uint8_t>& bit_lengths)
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{
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uint16_t bl_count[MAX_BITS] {};
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for (uint8_t bl : bit_lengths)
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bl_count[bl]++;
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bl_count[0] = 0;
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uint8_t min_bits = MAX_BITS;
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uint8_t max_bits = 0;
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for (uint8_t bits = 0; bits <= MAX_BITS; bits++)
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{
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if (bit_lengths[bits] == 0)
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continue;
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min_bits = BAN::Math::min(min_bits, bits);
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max_bits = BAN::Math::max(max_bits, bits);
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}
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uint8_t instant_max_bit = BAN::Math::min<uint8_t>(10, max_bits);
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uint16_t instant_mask = (1 << instant_max_bit) - 1;
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uint16_t code = 0;
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uint16_t next_code[MAX_BITS + 1] {};
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for (uint8_t bits = 1; bits <= max_bits; bits++)
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{
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code = (code + bl_count[bits - 1]) << 1;
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next_code[bits] = code;
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}
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BAN::Vector<Leaf> leaves;
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TRY(leaves.resize(1 << max_bits));
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for (uint16_t n = 0; n < bit_lengths.size(); n++)
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{
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uint8_t bits = bit_lengths[n];
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if (bits == 0)
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continue;
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uint16_t canonical = next_code[bits];
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next_code[bits]++;
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uint16_t reversed = reverse_bits(canonical, bits);
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leaves[reversed] = Leaf { n, bits };
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if (bits <= instant_max_bit)
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{
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uint16_t step = 1 << bits;
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for (uint16_t spread = reversed + step; spread <= instant_mask; spread += step)
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leaves[spread] = Leaf { n, bits };
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}
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}
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return HuffmanTree(BAN::move(leaves), min_bits, max_bits, instant_max_bit);
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}
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static BAN::ErrorOr<HuffmanTree> fixed_tree()
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{
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BAN::Vector<uint8_t> bit_lengths;
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TRY(bit_lengths.resize(288));
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size_t i = 0;
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for (; i <= 143; i++) bit_lengths[i] = 8;
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for (; i <= 255; i++) bit_lengths[i] = 9;
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for (; i <= 279; i++) bit_lengths[i] = 7;
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for (; i <= 287; i++) bit_lengths[i] = 8;
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return TRY(HuffmanTree::create(bit_lengths));
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}
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private:
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BAN::Vector<Leaf> m_leaves;
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uint8_t m_min_bits { 0 };
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uint8_t m_max_bits { 0 };
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uint8_t m_instant_max_bit { 0 };
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};
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class DeflateDecoder
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{
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public:
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DeflateDecoder(BAN::Vector<BAN::ConstByteSpan> data)
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: m_buffer(BinaryBuffer(BAN::move(data)))
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{}
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BAN::ErrorOr<BAN::ConstByteSpan> decode_stream()
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{
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while (!TRY(decode_block()))
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continue;
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return BAN::ConstByteSpan(m_decoded.span());
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}
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private:
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BAN::ErrorOr<bool> decode_block()
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{
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bool bfinal = TRY(m_buffer.get_bits(1));
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uint8_t btype = TRY(m_buffer.get_bits(2));
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switch (btype)
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{
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case 0: TRY(decode_type0()); break;
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case 1: TRY(decode_type1()); break;
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case 2: TRY(decode_type2()); break;
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default:
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dwarnln("Deflate block has invalid method {}", btype);
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return BAN::Error::from_errno(EINVAL);
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}
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return bfinal;
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}
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BAN::ErrorOr<void> decode_type0()
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{
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m_buffer.skip_to_byte_boundary();
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uint16_t len = TRY(m_buffer.get_bits(16));
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uint16_t nlen = TRY(m_buffer.get_bits(16));
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if (len != 0xFFFF - nlen)
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{
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dwarnln("Deflate block uncompressed data length is invalid");
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return BAN::Error::from_errno(EINVAL);
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}
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TRY(m_decoded.reserve(m_decoded.size() + len));
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for (uint16_t i = 0; i < len; i++)
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MUST(m_decoded.push_back(TRY(m_buffer.get_bits(8))));
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return {};
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}
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BAN::ErrorOr<void> decode_type1()
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{
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TRY(inflate_block(TRY(HuffmanTree::fixed_tree()), HuffmanTree()));
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return {};
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}
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BAN::ErrorOr<void> decode_type2()
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{
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static constexpr uint8_t code_length_order[] {
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16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15
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};
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const uint16_t hlit = TRY(m_buffer.get_bits(5)) + 257;
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const uint8_t hdist = TRY(m_buffer.get_bits(5)) + 1;
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const uint8_t hclen = TRY(m_buffer.get_bits(4)) + 4;
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HuffmanTree code_length_tree;
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{
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BAN::Vector<uint8_t> code_lengths;
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TRY(code_lengths.resize(19, 0));
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for (uint8_t i = 0; i < hclen; i++)
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code_lengths[code_length_order[i]] = TRY(m_buffer.get_bits(3));
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code_length_tree = TRY(HuffmanTree::create(code_lengths));
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}
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uint16_t last_symbol = 0;
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BAN::Vector<uint8_t> bit_lengths;
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TRY(bit_lengths.reserve(288 + 32));
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while (bit_lengths.size() < hlit + hdist)
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{
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uint16_t symbol = TRY(read_symbol(code_length_tree));
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uint8_t count = 0;
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if (symbol <= 15)
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{
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count = 1;
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}
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else if (symbol == 16)
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{
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symbol = last_symbol;
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count = TRY(m_buffer.get_bits(2)) + 3;
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}
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else if (symbol == 17)
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{
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symbol = 0;
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count = TRY(m_buffer.get_bits(3)) + 3;
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}
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else if (symbol == 18)
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{
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symbol = 0;
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count = TRY(m_buffer.get_bits(7)) + 11;
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}
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for (uint8_t i = 0; i < count; i++)
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TRY(bit_lengths.push_back(symbol));
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last_symbol = symbol;
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}
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TRY(bit_lengths.resize(hlit + 32, 0));
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BAN::Vector<uint8_t> distance_lengths;
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TRY(distance_lengths.resize(32));
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for (uint8_t i = 0; i < 32; i++)
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distance_lengths[i] = bit_lengths[hlit + i];
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TRY(bit_lengths.resize(hlit));
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TRY(bit_lengths.resize(288, 0));
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TRY(inflate_block(TRY(HuffmanTree::create(bit_lengths)), TRY(HuffmanTree::create(distance_lengths))));
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return {};
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}
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BAN::ErrorOr<void> inflate_block(const HuffmanTree& length_tree, const HuffmanTree& distance_tree)
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{
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static constexpr uint16_t length_base[] {
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3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258
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};
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static constexpr uint8_t extra_length_bits[] {
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0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0
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};
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static constexpr uint16_t distance_base[] {
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1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577
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};
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static constexpr uint8_t extra_distance_bits[] {
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0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13
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};
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uint16_t symbol;
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while ((symbol = TRY(read_symbol(length_tree))) != 256)
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{
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if (symbol < 256)
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{
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TRY(m_decoded.push_back(symbol));
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continue;
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}
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ASSERT(symbol <= 285);
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symbol -= 257;
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const uint16_t length = length_base[symbol] + TRY(m_buffer.get_bits(extra_length_bits[symbol]));
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uint16_t distance_code;
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if (distance_tree.empty())
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distance_code = reverse_bits(TRY(m_buffer.get_bits(5)), 5);
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else
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distance_code = TRY(read_symbol(distance_tree));
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ASSERT(distance_code <= 30);
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const size_t distance = distance_base[distance_code] + TRY(m_buffer.get_bits(extra_distance_bits[distance_code]));
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size_t offset = m_decoded.size() - distance;
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for (size_t i = 0; i < length; i++)
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TRY(m_decoded.push_back(m_decoded[offset + i]));
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}
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return {};
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}
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BAN::ErrorOr<uint16_t> read_symbol(const HuffmanTree& tree)
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{
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uint16_t compare = TRY(m_buffer.peek_bits(tree.max_bits()));
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for (uint8_t bits = tree.instant_max_bit(); bits <= tree.max_bits(); bits++)
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{
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uint16_t mask = (1 << bits) - 1;
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auto leaf = tree.get_leaf(compare & mask);
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if (leaf.len <= bits)
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{
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m_buffer.remove_bits(leaf.len);
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return leaf.code;
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}
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}
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return BAN::Error::from_errno(EINVAL);
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}
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private:
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BAN::Vector<uint8_t> m_decoded;
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BinaryBuffer m_buffer;
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};
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BAN::ErrorOr<PNGChunk> read_and_take_chunk(BAN::ConstByteSpan& image_data)
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{
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if (image_data.size() < 12)
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{
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dwarnln("PNG stream does not contain any more chunks");
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return BAN::Error::from_errno(EINVAL);
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}
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uint32_t length = image_data.as<const BAN::NetworkEndian<uint32_t>>();
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image_data = image_data.slice(4);
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if (image_data.size() < length + 8)
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{
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dwarnln("PNG stream does not contain any more chunks");
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return BAN::Error::from_errno(EINVAL);
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}
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PNGChunk result;
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result.name = BAN::StringView(image_data.as_span<const char>().data(), 4);
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image_data = image_data.slice(4);
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// skip chunk data
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result.data = image_data.slice(0, length);
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image_data = image_data.slice(length);
|
||||
|
||||
// FIXME: validate CRC
|
||||
image_data = image_data.slice(4);
|
||||
|
||||
return result;
|
||||
}
|
||||
|
||||
static bool validate_ihdr_colour_type_and_bit_depth(const IHDR& ihdr)
|
||||
{
|
||||
if (!BAN::Math::is_power_of_two(ihdr.bit_depth))
|
||||
return false;
|
||||
switch (ihdr.colour_type)
|
||||
{
|
||||
case ColourType::Greyscale:
|
||||
if (ihdr.bit_depth < 1 || ihdr.bit_depth > 16)
|
||||
return false;
|
||||
return true;
|
||||
case ColourType::Truecolour:
|
||||
if (ihdr.bit_depth < 8 || ihdr.bit_depth > 16)
|
||||
return false;
|
||||
return true;
|
||||
case ColourType::IndexedColour:
|
||||
if (ihdr.bit_depth < 1 || ihdr.bit_depth > 8)
|
||||
return false;
|
||||
return true;
|
||||
case ColourType::GreyscaleAlpha:
|
||||
if (ihdr.bit_depth < 8 || ihdr.bit_depth > 16)
|
||||
return false;
|
||||
return true;
|
||||
case ColourType::TruecolourAlpha:
|
||||
if (ihdr.bit_depth < 8 || ihdr.bit_depth > 16)
|
||||
return false;
|
||||
return true;
|
||||
default:
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
bool probe_png(BAN::ConstByteSpan image_data)
|
||||
{
|
||||
if (image_data.size() < 8)
|
||||
return false;
|
||||
uint64_t u64_signature = image_data.as<const uint64_t>();
|
||||
return u64_signature == 0x0A1A0A0D474E5089;
|
||||
}
|
||||
|
||||
BAN::ErrorOr<BAN::UniqPtr<Image>> load_png(BAN::ConstByteSpan image_data)
|
||||
{
|
||||
if (!probe_png(image_data))
|
||||
{
|
||||
dwarnln("Invalid PNG data");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
image_data = image_data.slice(8);
|
||||
|
||||
auto ihdr_chunk = TRY(read_and_take_chunk(image_data));
|
||||
if (ihdr_chunk.name != "IHDR")
|
||||
{
|
||||
dwarnln("PNG stream does not start with IHDR chunk");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (ihdr_chunk.data.size() != sizeof(IHDR))
|
||||
{
|
||||
dwarnln("PNG stream has invalid IHDR chunk size: {}, expected {}", ihdr_chunk.data.size(), sizeof(IHDR));
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
|
||||
const auto& ihdr = ihdr_chunk.data.as<const IHDR>();
|
||||
if (ihdr.width == 0 || ihdr.height == 0 || ihdr.width > 0x7FFFFFFF || ihdr.height > 0x7FFFFFFF)
|
||||
{
|
||||
dwarnln("PNG IHDR has invalid size {}x{}", (uint32_t)ihdr.width, (uint32_t)ihdr.height);
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (!validate_ihdr_colour_type_and_bit_depth(ihdr))
|
||||
{
|
||||
dwarnln("PNG IHDR has invalid bit depth {} for colour type {}", ihdr.bit_depth, static_cast<uint8_t>(ihdr.colour_type));
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (ihdr.compression_method != CompressionMethod::Deflate)
|
||||
{
|
||||
dwarnln("PNG IHDR has invalid compression method {}", static_cast<uint8_t>(ihdr.compression_method));
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (ihdr.filter_method != FilterMethod::Adaptive)
|
||||
{
|
||||
dwarnln("PNG IHDR has invalid filter method {}", static_cast<uint8_t>(ihdr.filter_method));
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (ihdr.interlace_method != InterlaceMethod::NoInterlace && ihdr.interlace_method != InterlaceMethod::Adam7)
|
||||
{
|
||||
dwarnln("PNG IHDR has invalid interlace method {}", static_cast<uint8_t>(ihdr.interlace_method));
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
|
||||
dprintln("Decoding {}x{} PNG image", (uint32_t)ihdr.width, (uint32_t)ihdr.height);
|
||||
dprintln(" bit depth: {}", ihdr.bit_depth);
|
||||
dprintln(" colour type: {}", static_cast<uint8_t>(ihdr.colour_type));
|
||||
dprintln(" compression method: {}", static_cast<uint8_t>(ihdr.compression_method));
|
||||
dprintln(" filter method: {}", static_cast<uint8_t>(ihdr.filter_method));
|
||||
dprintln(" interlace method: {}", static_cast<uint8_t>(ihdr.interlace_method));
|
||||
|
||||
BAN::Vector<PaletteEntry> palette;
|
||||
BAN::Vector<BAN::ConstByteSpan> zlib_stream;
|
||||
|
||||
while (true)
|
||||
{
|
||||
PNGChunk chunk;
|
||||
if (auto ret = read_and_take_chunk(image_data); !ret.is_error())
|
||||
chunk = ret.release_value();
|
||||
else
|
||||
{
|
||||
dwarnln("PNG stream does not end with IEND chunk");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
|
||||
if (chunk.name == "IHDR"sv)
|
||||
{
|
||||
dwarnln("PNG stream has IDHR chunk defined multiple times");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
else if (chunk.name == "PLTE"sv)
|
||||
{
|
||||
if (chunk.data.size() == 0 || chunk.data.size() % 3)
|
||||
{
|
||||
dwarnln("PNG PLTE has invalid data size {}", chunk.data.size());
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (!palette.empty())
|
||||
{
|
||||
dwarnln("PNG PLTE defined multiple times");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (ihdr.colour_type != ColourType::IndexedColour && ihdr.colour_type != ColourType::Truecolour && ihdr.colour_type != ColourType::TruecolourAlpha)
|
||||
{
|
||||
dwarnln("PNG PLTE defined for colour type {} which does not use palette", static_cast<uint8_t>(ihdr.colour_type));
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
TRY(palette.resize(chunk.data.size() / 3));
|
||||
for (size_t i = 0; i < palette.size(); i++)
|
||||
palette[i] = chunk.data.as_span<const PaletteEntry>()[i];
|
||||
}
|
||||
else if (chunk.name == "IDAT"sv)
|
||||
{
|
||||
TRY(zlib_stream.push_back(chunk.data));
|
||||
}
|
||||
else if (chunk.name == "IEND"sv)
|
||||
{
|
||||
break;
|
||||
}
|
||||
else if (chunk.name == "tEXt"sv)
|
||||
{
|
||||
auto data_sv = BAN::StringView(chunk.data.as_span<const char>().data(), chunk.data.size());
|
||||
if (auto idx = data_sv.find('\0'); !idx.has_value())
|
||||
dwarnln("PNG tEXt chunk does not contain null-byte");
|
||||
else
|
||||
{
|
||||
auto keyword = data_sv.substring(0, idx.value());
|
||||
auto text = data_sv.substring(idx.value() + 1);
|
||||
dprintln("'{}': '{}'", keyword, text);
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
bool ancillary = islower(chunk.name[0]);
|
||||
if (!ancillary)
|
||||
{
|
||||
dwarnln("Unsupported critical chunk '{}'", chunk.name);
|
||||
return BAN::Error::from_errno(ENOTSUP);
|
||||
}
|
||||
dwarnln("Skipping unsupported ancillary chunk '{}'", chunk.name);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
{
|
||||
if (zlib_stream.empty() || zlib_stream.front().size() < 2)
|
||||
{
|
||||
dwarnln("PNG does not have zlib stream");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (zlib_stream[0].as<const BAN::BigEndian<uint16_t>>() % 31)
|
||||
{
|
||||
dwarnln("PNG zlib stream checksum failed");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
|
||||
auto zlib_header = zlib_stream[0].as<const ZLibStream>();
|
||||
if (zlib_header.fdict)
|
||||
{
|
||||
dwarnln("PNG IDAT zlib stream has fdict set");
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
if (zlib_header.cm != 8)
|
||||
{
|
||||
dwarnln("PNG IDAT has invalid zlib compression method {}", (uint8_t)zlib_header.cm);
|
||||
return BAN::Error::from_errno(EINVAL);
|
||||
}
|
||||
zlib_stream[0] = zlib_stream[0].slice(2);
|
||||
}
|
||||
|
||||
uint64_t total_size = 0;
|
||||
for (auto stream : zlib_stream)
|
||||
total_size += stream.size();
|
||||
dprintln("PNG has {} byte zlib stream", total_size);
|
||||
|
||||
DeflateDecoder decoder(BAN::move(zlib_stream));
|
||||
auto decoded = TRY(decoder.decode_stream());
|
||||
|
||||
dprintln(" uncompressed size {}", decoded.size());
|
||||
dprintln(" compression ratio {}", (double)decoded.size() / total_size);
|
||||
|
||||
return BAN::Error::from_errno(ENOTSUP);
|
||||
}
|
||||
|
||||
}
|
||||
|
|
@ -0,0 +1,11 @@
|
|||
#include <BAN/ByteSpan.h>
|
||||
|
||||
#include <LibImage/Image.h>
|
||||
|
||||
namespace LibImage
|
||||
{
|
||||
|
||||
bool probe_png(BAN::ConstByteSpan);
|
||||
BAN::ErrorOr<BAN::UniqPtr<Image>> load_png(BAN::ConstByteSpan);
|
||||
|
||||
}
|
||||
Loading…
Reference in New Issue