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Diffstat (limited to 'thirdparty/jpeg-compressor/jpge.h')
| -rw-r--r-- | thirdparty/jpeg-compressor/jpge.h | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/thirdparty/jpeg-compressor/jpge.h b/thirdparty/jpeg-compressor/jpge.h new file mode 100644 index 0000000000..d10510e553 --- /dev/null +++ b/thirdparty/jpeg-compressor/jpge.h @@ -0,0 +1,174 @@ +// jpge.h - C++ class for JPEG compression. +// Public Domain or Apache 2.0, Richard Geldreich <richgel99@gmail.com> +// Alex Evans: Added RGBA support, linear memory allocator. +#ifndef JPEG_ENCODER_H +#define JPEG_ENCODER_H + +namespace jpge +{ + typedef unsigned char uint8; + typedef signed short int16; + typedef signed int int32; + typedef unsigned short uint16; + typedef unsigned int uint32; + typedef unsigned int uint; + + // JPEG chroma subsampling factors. Y_ONLY (grayscale images) and H2V2 (color images) are the most common. + enum subsampling_t { Y_ONLY = 0, H1V1 = 1, H2V1 = 2, H2V2 = 3 }; + + // JPEG compression parameters structure. + struct params + { + inline params() : m_quality(85), m_subsampling(H2V2), m_no_chroma_discrim_flag(false), m_two_pass_flag(false), m_use_std_tables(false) { } + + inline bool check() const + { + if ((m_quality < 1) || (m_quality > 100)) return false; + if ((uint)m_subsampling > (uint)H2V2) return false; + return true; + } + + // Quality: 1-100, higher is better. Typical values are around 50-95. + int m_quality; + + // m_subsampling: + // 0 = Y (grayscale) only + // 1 = YCbCr, no subsampling (H1V1, YCbCr 1x1x1, 3 blocks per MCU) + // 2 = YCbCr, H2V1 subsampling (YCbCr 2x1x1, 4 blocks per MCU) + // 3 = YCbCr, H2V2 subsampling (YCbCr 4x1x1, 6 blocks per MCU-- very common) + subsampling_t m_subsampling; + + // Disables CbCr discrimination - only intended for testing. + // If true, the Y quantization table is also used for the CbCr channels. + bool m_no_chroma_discrim_flag; + + bool m_two_pass_flag; + + // By default we use the same quantization tables as mozjpeg's default. + // Set to true to use the traditional tables from JPEG Annex K. + bool m_use_std_tables; + }; + + // Writes JPEG image to a file. + // num_channels must be 1 (Y) or 3 (RGB), image pitch must be width*num_channels. + bool compress_image_to_jpeg_file(const char* pFilename, int width, int height, int num_channels, const uint8* pImage_data, const params& comp_params = params()); + + // Writes JPEG image to memory buffer. + // On entry, buf_size is the size of the output buffer pointed at by pBuf, which should be at least ~1024 bytes. + // If return value is true, buf_size will be set to the size of the compressed data. + bool compress_image_to_jpeg_file_in_memory(void* pBuf, int& buf_size, int width, int height, int num_channels, const uint8* pImage_data, const params& comp_params = params()); + + // Output stream abstract class - used by the jpeg_encoder class to write to the output stream. + // put_buf() is generally called with len==JPGE_OUT_BUF_SIZE bytes, but for headers it'll be called with smaller amounts. + class output_stream + { + public: + virtual ~output_stream() { }; + virtual bool put_buf(const void* Pbuf, int len) = 0; + template<class T> inline bool put_obj(const T& obj) { return put_buf(&obj, sizeof(T)); } + }; + + // Lower level jpeg_encoder class - useful if more control is needed than the above helper functions. + class jpeg_encoder + { + public: + jpeg_encoder(); + ~jpeg_encoder(); + + // Initializes the compressor. + // pStream: The stream object to use for writing compressed data. + // params - Compression parameters structure, defined above. + // width, height - Image dimensions. + // channels - May be 1, or 3. 1 indicates grayscale, 3 indicates RGB source data. + // Returns false on out of memory or if a stream write fails. + bool init(output_stream* pStream, int width, int height, int src_channels, const params& comp_params = params()); + + const params& get_params() const { return m_params; } + + // Deinitializes the compressor, freeing any allocated memory. May be called at any time. + void deinit(); + + uint get_total_passes() const { return m_params.m_two_pass_flag ? 2 : 1; } + inline uint get_cur_pass() { return m_pass_num; } + + // Call this method with each source scanline. + // width * src_channels bytes per scanline is expected (RGB or Y format). + // You must call with NULL after all scanlines are processed to finish compression. + // Returns false on out of memory or if a stream write fails. + bool process_scanline(const void* pScanline); + + private: + jpeg_encoder(const jpeg_encoder&); + jpeg_encoder& operator =(const jpeg_encoder&); + + typedef int32 sample_array_t; + + output_stream* m_pStream; + params m_params; + uint8 m_num_components; + uint8 m_comp_h_samp[3], m_comp_v_samp[3]; + int m_image_x, m_image_y, m_image_bpp, m_image_bpl; + int m_image_x_mcu, m_image_y_mcu; + int m_image_bpl_xlt, m_image_bpl_mcu; + int m_mcus_per_row; + int m_mcu_x, m_mcu_y; + uint8* m_mcu_lines[16]; + uint8 m_mcu_y_ofs; + sample_array_t m_sample_array[64]; + int16 m_coefficient_array[64]; + int32 m_quantization_tables[2][64]; + uint m_huff_codes[4][256]; + uint8 m_huff_code_sizes[4][256]; + uint8 m_huff_bits[4][17]; + uint8 m_huff_val[4][256]; + uint32 m_huff_count[4][256]; + int m_last_dc_val[3]; + enum { JPGE_OUT_BUF_SIZE = 2048 }; + uint8 m_out_buf[JPGE_OUT_BUF_SIZE]; + uint8* m_pOut_buf; + uint m_out_buf_left; + uint32 m_bit_buffer; + uint m_bits_in; + uint8 m_pass_num; + bool m_all_stream_writes_succeeded; + + void optimize_huffman_table(int table_num, int table_len); + void emit_byte(uint8 i); + void emit_word(uint i); + void emit_marker(int marker); + void emit_jfif_app0(); + void emit_dqt(); + void emit_sof(); + void emit_dht(uint8* bits, uint8* val, int index, bool ac_flag); + void emit_dhts(); + void emit_sos(); + void emit_markers(); + void compute_huffman_table(uint* codes, uint8* code_sizes, uint8* bits, uint8* val); + void compute_quant_table(int32* dst, int16* src); + void adjust_quant_table(int32* dst, int32* src); + void first_pass_init(); + bool second_pass_init(); + bool jpg_open(int p_x_res, int p_y_res, int src_channels); + void load_block_8_8_grey(int x); + void load_block_8_8(int x, int y, int c); + void load_block_16_8(int x, int c); + void load_block_16_8_8(int x, int c); + void load_quantized_coefficients(int component_num); + void flush_output_buffer(); + void put_bits(uint bits, uint len); + void code_coefficients_pass_one(int component_num); + void code_coefficients_pass_two(int component_num); + void code_block(int component_num); + void process_mcu_row(); + bool terminate_pass_one(); + bool terminate_pass_two(); + bool process_end_of_image(); + void load_mcu(const void* src); + void clear(); + void init(); + }; + +} // namespace jpge + +#endif // JPEG_ENCODER + |