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 /*

  * jcparam.c

  *

  * This file was part of the Independent JPEG Group's software:

  * Copyright (C) 1991-1998, Thomas G. Lane.

  * Modified 2003-2008 by Guido Vollbeding.

  * libjpeg-turbo Modifications:

  * Copyright (C) 2009-2011, D. R. Commander.

  * For conditions of distribution and use, see the accompanying README file.

  *

  * This file contains optional default-setting code for the JPEG compressor.

  * Applications do not have to use this file, but those that don't use it

  * must know a lot more about the innards of the JPEG code.

  */

 #define JPEG_INTERNALS

 #include "jinclude.h"

 #include "jpeglib.h"

 #include "jstdhuff.c"

 /*

  * Quantization table setup routines

  */

 GLOBAL(void)

 jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl,

 		      const unsigned int *basic_table,

 		      int scale_factor, boolean force_baseline)

 /* Define a quantization table equal to the basic_table times

  * a scale factor (given as a percentage).

  * If force_baseline is TRUE, the computed quantization table entries

  * are limited to 1..255 for JPEG baseline compatibility.

  */

 {

   JQUANT_TBL ** qtblptr;

   int i;

   long temp;

   /* Safety check to ensure start_compress not called yet. */

   if (cinfo->global_state != CSTATE_START)

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   if (which_tbl < 0 || which_tbl >= NUM_QUANT_TBLS)

     ERREXIT1(cinfo, JERR_DQT_INDEX, which_tbl);

   qtblptr = & cinfo->quant_tbl_ptrs[which_tbl];

   if (*qtblptr == NULL)

     *qtblptr = jpeg_alloc_quant_table((j_common_ptr) cinfo);

   for (i = 0; i < DCTSIZE2; i++) {

     temp = ((long) basic_table[i] * scale_factor + 50L) / 100L;

     /* limit the values to the valid range */

     if (temp <= 0L) temp = 1L;

     if (temp > 32767L) temp = 32767L; /* max quantizer needed for 12 bits */

     if (force_baseline && temp > 255L)

       temp = 255L;		/* limit to baseline range if requested */

     (*qtblptr)->quantval[i] = (UINT16) temp;

   }

   /* Initialize sent_table FALSE so table will be written to JPEG file. */

   (*qtblptr)->sent_table = FALSE;

 }

 /* These are the sample quantization tables given in JPEG spec section K.1.

  * The spec says that the values given produce "good" quality, and

  * when divided by 2, "very good" quality.

  */

 static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {

   16,  11,  10,  16,  24,  40,  51,  61,

   12,  12,  14,  19,  26,  58,  60,  55,

   14,  13,  16,  24,  40,  57,  69,  56,

   14,  17,  22,  29,  51,  87,  80,  62,

   18,  22,  37,  56,  68, 109, 103,  77,

   24,  35,  55,  64,  81, 104, 113,  92,

   49,  64,  78,  87, 103, 121, 120, 101,

   72,  92,  95,  98, 112, 100, 103,  99

 };

 static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {

   17,  18,  24,  47,  99,  99,  99,  99,

   18,  21,  26,  66,  99,  99,  99,  99,

   24,  26,  56,  99,  99,  99,  99,  99,

   47,  66,  99,  99,  99,  99,  99,  99,

   99,  99,  99,  99,  99,  99,  99,  99,

   99,  99,  99,  99,  99,  99,  99,  99,

   99,  99,  99,  99,  99,  99,  99,  99,

   99,  99,  99,  99,  99,  99,  99,  99

 };

 #if JPEG_LIB_VERSION >= 70

 GLOBAL(void)

 jpeg_default_qtables (j_compress_ptr cinfo, boolean force_baseline)

 /* Set or change the 'quality' (quantization) setting, using default tables

  * and straight percentage-scaling quality scales.

  * This entry point allows different scalings for luminance and chrominance.

  */

 {

   /* Set up two quantization tables using the specified scaling */

   jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,

 		       cinfo->q_scale_factor[0], force_baseline);

   jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,

 		       cinfo->q_scale_factor[1], force_baseline);

 }

 #endif

 GLOBAL(void)

 jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor,

 			 boolean force_baseline)

 /* Set or change the 'quality' (quantization) setting, using default tables

  * and a straight percentage-scaling quality scale.  In most cases it's better

  * to use jpeg_set_quality (below); this entry point is provided for

  * applications that insist on a linear percentage scaling.

  */

 {

   /* Set up two quantization tables using the specified scaling */

   jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,

 		       scale_factor, force_baseline);

   jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,

 		       scale_factor, force_baseline);

 }

 GLOBAL(int)

 jpeg_quality_scaling (int quality)

 /* Convert a user-specified quality rating to a percentage scaling factor

  * for an underlying quantization table, using our recommended scaling curve.

  * The input 'quality' factor should be 0 (terrible) to 100 (very good).

  */

 {

   /* Safety limit on quality factor.  Convert 0 to 1 to avoid zero divide. */

   if (quality <= 0) quality = 1;

   if (quality > 100) quality = 100;

   /* The basic table is used as-is (scaling 100) for a quality of 50.

    * Qualities 50..100 are converted to scaling percentage 200 - 2*Q;

    * note that at Q=100 the scaling is 0, which will cause jpeg_add_quant_table

    * to make all the table entries 1 (hence, minimum quantization loss).

    * Qualities 1..50 are converted to scaling percentage 5000/Q.

    */

   if (quality < 50)

     quality = 5000 / quality;

   else

     quality = 200 - quality*2;

   return quality;

 }

 GLOBAL(void)

 jpeg_set_quality (j_compress_ptr cinfo, int quality, boolean force_baseline)

 /* Set or change the 'quality' (quantization) setting, using default tables.

  * This is the standard quality-adjusting entry point for typical user

  * interfaces; only those who want detailed control over quantization tables

  * would use the preceding three routines directly.

  */

 {

   /* Convert user 0-100 rating to percentage scaling */

   quality = jpeg_quality_scaling(quality);

   /* Set up standard quality tables */

   jpeg_set_linear_quality(cinfo, quality, force_baseline);

 }

 /*

  * Default parameter setup for compression.

  *

  * Applications that don't choose to use this routine must do their

  * own setup of all these parameters.  Alternately, you can call this

  * to establish defaults and then alter parameters selectively.  This

  * is the recommended approach since, if we add any new parameters,

  * your code will still work (they'll be set to reasonable defaults).

  */

 GLOBAL(void)

 jpeg_set_defaults (j_compress_ptr cinfo)

 {

   int i;

   /* Safety check to ensure start_compress not called yet. */

   if (cinfo->global_state != CSTATE_START)

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   /* Allocate comp_info array large enough for maximum component count.

    * Array is made permanent in case application wants to compress

    * multiple images at same param settings.

    */

   if (cinfo->comp_info == NULL)

     cinfo->comp_info = (jpeg_component_info *)

       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

 				  MAX_COMPONENTS * SIZEOF(jpeg_component_info));

   /* Initialize everything not dependent on the color space */

 #if JPEG_LIB_VERSION >= 70

   cinfo->scale_num = 1;		/* 1:1 scaling */

   cinfo->scale_denom = 1;

 #endif

   cinfo->data_precision = BITS_IN_JSAMPLE;

   /* Set up two quantization tables using default quality of 75 */

   jpeg_set_quality(cinfo, 75, TRUE);

   /* Set up two Huffman tables */

   std_huff_tables((j_common_ptr) cinfo);

   /* Initialize default arithmetic coding conditioning */

   for (i = 0; i < NUM_ARITH_TBLS; i++) {

     cinfo->arith_dc_L[i] = 0;

     cinfo->arith_dc_U[i] = 1;

     cinfo->arith_ac_K[i] = 5;

   }

   /* Default is no multiple-scan output */

   cinfo->scan_info = NULL;

   cinfo->num_scans = 0;

   /* Expect normal source image, not raw downsampled data */

   cinfo->raw_data_in = FALSE;

   /* Use Huffman coding, not arithmetic coding, by default */

   cinfo->arith_code = FALSE;

   /* By default, don't do extra passes to optimize entropy coding */

   cinfo->optimize_coding = FALSE;

   /* The standard Huffman tables are only valid for 8-bit data precision.

    * If the precision is higher, force optimization on so that usable

    * tables will be computed.  This test can be removed if default tables

    * are supplied that are valid for the desired precision.

    */

   if (cinfo->data_precision > 8)

     cinfo->optimize_coding = TRUE;

   /* By default, use the simpler non-cosited sampling alignment */

   cinfo->CCIR601_sampling = FALSE;

 #if JPEG_LIB_VERSION >= 70

   /* By default, apply fancy downsampling */

   cinfo->do_fancy_downsampling = TRUE;

 #endif

   /* No input smoothing */

   cinfo->smoothing_factor = 0;

   /* DCT algorithm preference */

   cinfo->dct_method = JDCT_DEFAULT;

   /* No restart markers */

   cinfo->restart_interval = 0;

   cinfo->restart_in_rows = 0;

   /* Fill in default JFIF marker parameters.  Note that whether the marker

    * will actually be written is determined by jpeg_set_colorspace.

    *

    * By default, the library emits JFIF version code 1.01.

    * An application that wants to emit JFIF 1.02 extension markers should set

    * JFIF_minor_version to 2.  We could probably get away with just defaulting

    * to 1.02, but there may still be some decoders in use that will complain

    * about that; saying 1.01 should minimize compatibility problems.

    */

   cinfo->JFIF_major_version = 1; /* Default JFIF version = 1.01 */

   cinfo->JFIF_minor_version = 1;

   cinfo->density_unit = 0;	/* Pixel size is unknown by default */

   cinfo->X_density = 1;		/* Pixel aspect ratio is square by default */

   cinfo->Y_density = 1;

   /* Choose JPEG colorspace based on input space, set defaults accordingly */

   jpeg_default_colorspace(cinfo);

 }

 /*

  * Select an appropriate JPEG colorspace for in_color_space.

  */

 GLOBAL(void)

 jpeg_default_colorspace (j_compress_ptr cinfo)

 {

   switch (cinfo->in_color_space) {

   case JCS_GRAYSCALE:

     jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);

     break;

   case JCS_RGB:

   case JCS_EXT_RGB:

   case JCS_EXT_RGBX:

   case JCS_EXT_BGR:

   case JCS_EXT_BGRX:

   case JCS_EXT_XBGR:

   case JCS_EXT_XRGB:

   case JCS_EXT_RGBA:

   case JCS_EXT_BGRA:

   case JCS_EXT_ABGR:

   case JCS_EXT_ARGB:

     jpeg_set_colorspace(cinfo, JCS_YCbCr);

     break;

   case JCS_YCbCr:

     jpeg_set_colorspace(cinfo, JCS_YCbCr);

     break;

   case JCS_CMYK:

     jpeg_set_colorspace(cinfo, JCS_CMYK); /* By default, no translation */

     break;

   case JCS_YCCK:

     jpeg_set_colorspace(cinfo, JCS_YCCK);

     break;

   case JCS_UNKNOWN:

     jpeg_set_colorspace(cinfo, JCS_UNKNOWN);

     break;

   default:

     ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);

   }

 }

 /*

  * Set the JPEG colorspace, and choose colorspace-dependent default values.

  */

 GLOBAL(void)

 jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace)

 {

   jpeg_component_info * compptr;

   int ci;

 #define SET_COMP(index,id,hsamp,vsamp,quant,dctbl,actbl)  \

   (compptr = &cinfo->comp_info[index], \

    compptr->component_id = (id), \

    compptr->h_samp_factor = (hsamp), \

    compptr->v_samp_factor = (vsamp), \

    compptr->quant_tbl_no = (quant), \

    compptr->dc_tbl_no = (dctbl), \

    compptr->ac_tbl_no = (actbl) )

   /* Safety check to ensure start_compress not called yet. */

   if (cinfo->global_state != CSTATE_START)

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   /* For all colorspaces, we use Q and Huff tables 0 for luminance components,

    * tables 1 for chrominance components.

    */

   cinfo->jpeg_color_space = colorspace;

   cinfo->write_JFIF_header = FALSE; /* No marker for non-JFIF colorspaces */

   cinfo->write_Adobe_marker = FALSE; /* write no Adobe marker by default */

   switch (colorspace) {

   case JCS_GRAYSCALE:

     cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */

     cinfo->num_components = 1;

     /* JFIF specifies component ID 1 */

     SET_COMP(0, 1, 1,1, 0, 0,0);

     break;

   case JCS_RGB:

     cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag RGB */

     cinfo->num_components = 3;

     SET_COMP(0, 0x52 /* 'R' */, 1,1, 0, 0,0);

     SET_COMP(1, 0x47 /* 'G' */, 1,1, 0, 0,0);

     SET_COMP(2, 0x42 /* 'B' */, 1,1, 0, 0,0);

     break;

   case JCS_YCbCr:

     cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */

     cinfo->num_components = 3;

     /* JFIF specifies component IDs 1,2,3 */

     /* We default to 2x2 subsamples of chrominance */

     SET_COMP(0, 1, 2,2, 0, 0,0);

     SET_COMP(1, 2, 1,1, 1, 1,1);

     SET_COMP(2, 3, 1,1, 1, 1,1);

     break;

   case JCS_CMYK:

     cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag CMYK */

     cinfo->num_components = 4;

     SET_COMP(0, 0x43 /* 'C' */, 1,1, 0, 0,0);

     SET_COMP(1, 0x4D /* 'M' */, 1,1, 0, 0,0);

     SET_COMP(2, 0x59 /* 'Y' */, 1,1, 0, 0,0);

     SET_COMP(3, 0x4B /* 'K' */, 1,1, 0, 0,0);

     break;

   case JCS_YCCK:

     cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag YCCK */

     cinfo->num_components = 4;

     SET_COMP(0, 1, 2,2, 0, 0,0);

     SET_COMP(1, 2, 1,1, 1, 1,1);

     SET_COMP(2, 3, 1,1, 1, 1,1);

     SET_COMP(3, 4, 2,2, 0, 0,0);

     break;

   case JCS_UNKNOWN:

     cinfo->num_components = cinfo->input_components;

     if (cinfo->num_components < 1 || cinfo->num_components > MAX_COMPONENTS)

       ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,

 	       MAX_COMPONENTS);

     for (ci = 0; ci < cinfo->num_components; ci++) {

       SET_COMP(ci, ci, 1,1, 0, 0,0);

     }

     break;

   default:

     ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);

   }

 }

 #ifdef C_PROGRESSIVE_SUPPORTED

 LOCAL(jpeg_scan_info *)

 fill_a_scan (jpeg_scan_info * scanptr, int ci,

 	     int Ss, int Se, int Ah, int Al)

 /* Support routine: generate one scan for specified component */

 {

   scanptr->comps_in_scan = 1;

   scanptr->component_index[0] = ci;

   scanptr->Ss = Ss;

   scanptr->Se = Se;

   scanptr->Ah = Ah;

   scanptr->Al = Al;

   scanptr++;

   return scanptr;

 }

 LOCAL(jpeg_scan_info *)

 fill_scans (jpeg_scan_info * scanptr, int ncomps,

 	    int Ss, int Se, int Ah, int Al)

 /* Support routine: generate one scan for each component */

 {

   int ci;

   for (ci = 0; ci < ncomps; ci++) {

     scanptr->comps_in_scan = 1;

     scanptr->component_index[0] = ci;

     scanptr->Ss = Ss;

     scanptr->Se = Se;

     scanptr->Ah = Ah;

     scanptr->Al = Al;

     scanptr++;

   }

   return scanptr;

 }

 LOCAL(jpeg_scan_info *)

 fill_dc_scans (jpeg_scan_info * scanptr, int ncomps, int Ah, int Al)

 /* Support routine: generate interleaved DC scan if possible, else N scans */

 {

   int ci;

   if (ncomps <= MAX_COMPS_IN_SCAN) {

     /* Single interleaved DC scan */

     scanptr->comps_in_scan = ncomps;

     for (ci = 0; ci < ncomps; ci++)

       scanptr->component_index[ci] = ci;

     scanptr->Ss = scanptr->Se = 0;

     scanptr->Ah = Ah;

     scanptr->Al = Al;

     scanptr++;

   } else {

     /* Noninterleaved DC scan for each component */

     scanptr = fill_scans(scanptr, ncomps, 0, 0, Ah, Al);

   }

   return scanptr;

 }

 /*

  * Create a recommended progressive-JPEG script.

  * cinfo->num_components and cinfo->jpeg_color_space must be correct.

  */

 GLOBAL(void)

 jpeg_simple_progression (j_compress_ptr cinfo)

 {

   int ncomps = cinfo->num_components;

   int nscans;

   jpeg_scan_info * scanptr;

   /* Safety check to ensure start_compress not called yet. */

   if (cinfo->global_state != CSTATE_START)

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   /* Figure space needed for script.  Calculation must match code below! */

   if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {

     /* Custom script for YCbCr color images. */

     nscans = 10;

   } else {

     /* All-purpose script for other color spaces. */

     if (ncomps > MAX_COMPS_IN_SCAN)

       nscans = 6 * ncomps;	/* 2 DC + 4 AC scans per component */

     else

       nscans = 2 + 4 * ncomps;	/* 2 DC scans; 4 AC scans per component */

   }

   /* Allocate space for script.

    * We need to put it in the permanent pool in case the application performs

    * multiple compressions without changing the settings.  To avoid a memory

    * leak if jpeg_simple_progression is called repeatedly for the same JPEG

    * object, we try to re-use previously allocated space, and we allocate

    * enough space to handle YCbCr even if initially asked for grayscale.

    */

   if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) {

     cinfo->script_space_size = MAX(nscans, 10);

     cinfo->script_space = (jpeg_scan_info *)

       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,

 			cinfo->script_space_size * SIZEOF(jpeg_scan_info));

   }

   scanptr = cinfo->script_space;

   cinfo->scan_info = scanptr;

   cinfo->num_scans = nscans;

   if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {

     /* Custom script for YCbCr color images. */

     /* Initial DC scan */

     scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);

     /* Initial AC scan: get some luma data out in a hurry */

     scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);

     /* Chroma data is too small to be worth expending many scans on */

     scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);

     scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);

     /* Complete spectral selection for luma AC */

     scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);

     /* Refine next bit of luma AC */

     scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);

     /* Finish DC successive approximation */

     scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);

     /* Finish AC successive approximation */

     scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);

     scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);

     /* Luma bottom bit comes last since it's usually largest scan */

     scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);

   } else {

     /* All-purpose script for other color spaces. */

     /* Successive approximation first pass */

     scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);

     scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);

     scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);

     /* Successive approximation second pass */

     scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);

     /* Successive approximation final pass */

     scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);

     scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);

   }

 }

 #endif /* C_PROGRESSIVE_SUPPORTED */