diff options
Diffstat (limited to 'jpeglib.h')
| -rw-r--r-- | jpeglib.h | 38 |
1 files changed, 32 insertions, 6 deletions
@@ -144,7 +144,8 @@ typedef struct { * Values of 1,2,4,8 are likely to be supported. Note that different * components may receive different IDCT scalings. */ - int DCT_scaled_size; + int DCT_h_scaled_size; + int DCT_v_scaled_size; /* The downsampled dimensions are the component's actual, unpadded number * of samples at the main buffer (preprocessing/compression interface), thus * downsampled_width = ceil(image_width * Hi/Hmax) @@ -291,6 +292,17 @@ struct jpeg_compress_struct { * helper routines to simplify changing parameters. */ + unsigned int scale_num, scale_denom; /* fraction by which to scale image */ + + JDIMENSION jpeg_width; /* scaled JPEG image width */ + JDIMENSION jpeg_height; /* scaled JPEG image height */ + /* Dimensions of actual JPEG image that will be written to file, + * derived from input dimensions by scaling factors above. + * These fields are computed by jpeg_start_compress(). + * You can also use jpeg_calc_jpeg_dimensions() to determine these values + * in advance of calling jpeg_start_compress(). + */ + int data_precision; /* bits of precision in image data */ int num_components; /* # of color components in JPEG image */ @@ -298,14 +310,17 @@ struct jpeg_compress_struct { jpeg_component_info * comp_info; /* comp_info[i] describes component that appears i'th in SOF */ - + JQUANT_TBL * quant_tbl_ptrs[NUM_QUANT_TBLS]; - /* ptrs to coefficient quantization tables, or NULL if not defined */ - + int q_scale_factor[NUM_QUANT_TBLS]; + /* ptrs to coefficient quantization tables, or NULL if not defined, + * and corresponding scale factors (percentage, initialized 100). + */ + JHUFF_TBL * dc_huff_tbl_ptrs[NUM_HUFF_TBLS]; JHUFF_TBL * ac_huff_tbl_ptrs[NUM_HUFF_TBLS]; /* ptrs to Huffman coding tables, or NULL if not defined */ - + UINT8 arith_dc_L[NUM_ARITH_TBLS]; /* L values for DC arith-coding tables */ UINT8 arith_dc_U[NUM_ARITH_TBLS]; /* U values for DC arith-coding tables */ UINT8 arith_ac_K[NUM_ARITH_TBLS]; /* Kx values for AC arith-coding tables */ @@ -364,6 +379,9 @@ struct jpeg_compress_struct { int max_h_samp_factor; /* largest h_samp_factor */ int max_v_samp_factor; /* largest v_samp_factor */ + int min_DCT_h_scaled_size; /* smallest DCT_scaled_size of any component */ + int min_DCT_v_scaled_size; /* smallest DCT_scaled_size of any component */ + JDIMENSION total_iMCU_rows; /* # of iMCU rows to be input to coef ctlr */ /* The coefficient controller receives data in units of MCU rows as defined * for fully interleaved scans (whether the JPEG file is interleaved or not). @@ -575,7 +593,8 @@ struct jpeg_decompress_struct { int max_h_samp_factor; /* largest h_samp_factor */ int max_v_samp_factor; /* largest v_samp_factor */ - int min_DCT_scaled_size; /* smallest DCT_scaled_size of any component */ + int min_DCT_h_scaled_size; /* smallest DCT_scaled_size of any component */ + int min_DCT_v_scaled_size; /* smallest DCT_scaled_size of any component */ JDIMENSION total_iMCU_rows; /* # of iMCU rows in image */ /* The coefficient controller's input and output progress is measured in @@ -841,6 +860,7 @@ typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); #define jpeg_default_colorspace jDefColorspace #define jpeg_set_quality jSetQuality #define jpeg_set_linear_quality jSetLQuality +#define jpeg_default_qtables jDefQTables #define jpeg_add_quant_table jAddQuantTable #define jpeg_quality_scaling jQualityScaling #define jpeg_simple_progression jSimProgress @@ -850,6 +870,7 @@ typedef JMETHOD(boolean, jpeg_marker_parser_method, (j_decompress_ptr cinfo)); #define jpeg_start_compress jStrtCompress #define jpeg_write_scanlines jWrtScanlines #define jpeg_finish_compress jFinCompress +#define jpeg_calc_jpeg_dimensions jCjpegDimensions #define jpeg_write_raw_data jWrtRawData #define jpeg_write_marker jWrtMarker #define jpeg_write_m_header jWrtMHeader @@ -921,6 +942,8 @@ EXTERN(void) jpeg_set_quality JPP((j_compress_ptr cinfo, int quality, EXTERN(void) jpeg_set_linear_quality JPP((j_compress_ptr cinfo, int scale_factor, boolean force_baseline)); +EXTERN(void) jpeg_default_qtables JPP((j_compress_ptr cinfo, + boolean force_baseline)); EXTERN(void) jpeg_add_quant_table JPP((j_compress_ptr cinfo, int which_tbl, const unsigned int *basic_table, int scale_factor, @@ -940,6 +963,9 @@ EXTERN(JDIMENSION) jpeg_write_scanlines JPP((j_compress_ptr cinfo, JDIMENSION num_lines)); EXTERN(void) jpeg_finish_compress JPP((j_compress_ptr cinfo)); +/* Precalculate JPEG dimensions for current compression parameters. */ +EXTERN(void) jpeg_calc_jpeg_dimensions JPP((j_compress_ptr cinfo)); + /* Replaces jpeg_write_scanlines when writing raw downsampled data. */ EXTERN(JDIMENSION) jpeg_write_raw_data JPP((j_compress_ptr cinfo, JSAMPIMAGE data, |