1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libjpeg/jcparam.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,541 @@
1.4 +/*
1.5 + * jcparam.c
1.6 + *
1.7 + * This file was part of the Independent JPEG Group's software:
1.8 + * Copyright (C) 1991-1998, Thomas G. Lane.
1.9 + * Modified 2003-2008 by Guido Vollbeding.
1.10 + * libjpeg-turbo Modifications:
1.11 + * Copyright (C) 2009-2011, D. R. Commander.
1.12 + * For conditions of distribution and use, see the accompanying README file.
1.13 + *
1.14 + * This file contains optional default-setting code for the JPEG compressor.
1.15 + * Applications do not have to use this file, but those that don't use it
1.16 + * must know a lot more about the innards of the JPEG code.
1.17 + */
1.18 +
1.19 +#define JPEG_INTERNALS
1.20 +#include "jinclude.h"
1.21 +#include "jpeglib.h"
1.22 +#include "jstdhuff.c"
1.23 +
1.24 +
1.25 +/*
1.26 + * Quantization table setup routines
1.27 + */
1.28 +
1.29 +GLOBAL(void)
1.30 +jpeg_add_quant_table (j_compress_ptr cinfo, int which_tbl,
1.31 + const unsigned int *basic_table,
1.32 + int scale_factor, boolean force_baseline)
1.33 +/* Define a quantization table equal to the basic_table times
1.34 + * a scale factor (given as a percentage).
1.35 + * If force_baseline is TRUE, the computed quantization table entries
1.36 + * are limited to 1..255 for JPEG baseline compatibility.
1.37 + */
1.38 +{
1.39 + JQUANT_TBL ** qtblptr;
1.40 + int i;
1.41 + long temp;
1.42 +
1.43 + /* Safety check to ensure start_compress not called yet. */
1.44 + if (cinfo->global_state != CSTATE_START)
1.45 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
1.46 +
1.47 + if (which_tbl < 0 || which_tbl >= NUM_QUANT_TBLS)
1.48 + ERREXIT1(cinfo, JERR_DQT_INDEX, which_tbl);
1.49 +
1.50 + qtblptr = & cinfo->quant_tbl_ptrs[which_tbl];
1.51 +
1.52 + if (*qtblptr == NULL)
1.53 + *qtblptr = jpeg_alloc_quant_table((j_common_ptr) cinfo);
1.54 +
1.55 + for (i = 0; i < DCTSIZE2; i++) {
1.56 + temp = ((long) basic_table[i] * scale_factor + 50L) / 100L;
1.57 + /* limit the values to the valid range */
1.58 + if (temp <= 0L) temp = 1L;
1.59 + if (temp > 32767L) temp = 32767L; /* max quantizer needed for 12 bits */
1.60 + if (force_baseline && temp > 255L)
1.61 + temp = 255L; /* limit to baseline range if requested */
1.62 + (*qtblptr)->quantval[i] = (UINT16) temp;
1.63 + }
1.64 +
1.65 + /* Initialize sent_table FALSE so table will be written to JPEG file. */
1.66 + (*qtblptr)->sent_table = FALSE;
1.67 +}
1.68 +
1.69 +
1.70 +/* These are the sample quantization tables given in JPEG spec section K.1.
1.71 + * The spec says that the values given produce "good" quality, and
1.72 + * when divided by 2, "very good" quality.
1.73 + */
1.74 +static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = {
1.75 + 16, 11, 10, 16, 24, 40, 51, 61,
1.76 + 12, 12, 14, 19, 26, 58, 60, 55,
1.77 + 14, 13, 16, 24, 40, 57, 69, 56,
1.78 + 14, 17, 22, 29, 51, 87, 80, 62,
1.79 + 18, 22, 37, 56, 68, 109, 103, 77,
1.80 + 24, 35, 55, 64, 81, 104, 113, 92,
1.81 + 49, 64, 78, 87, 103, 121, 120, 101,
1.82 + 72, 92, 95, 98, 112, 100, 103, 99
1.83 +};
1.84 +static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = {
1.85 + 17, 18, 24, 47, 99, 99, 99, 99,
1.86 + 18, 21, 26, 66, 99, 99, 99, 99,
1.87 + 24, 26, 56, 99, 99, 99, 99, 99,
1.88 + 47, 66, 99, 99, 99, 99, 99, 99,
1.89 + 99, 99, 99, 99, 99, 99, 99, 99,
1.90 + 99, 99, 99, 99, 99, 99, 99, 99,
1.91 + 99, 99, 99, 99, 99, 99, 99, 99,
1.92 + 99, 99, 99, 99, 99, 99, 99, 99
1.93 +};
1.94 +
1.95 +
1.96 +#if JPEG_LIB_VERSION >= 70
1.97 +GLOBAL(void)
1.98 +jpeg_default_qtables (j_compress_ptr cinfo, boolean force_baseline)
1.99 +/* Set or change the 'quality' (quantization) setting, using default tables
1.100 + * and straight percentage-scaling quality scales.
1.101 + * This entry point allows different scalings for luminance and chrominance.
1.102 + */
1.103 +{
1.104 + /* Set up two quantization tables using the specified scaling */
1.105 + jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,
1.106 + cinfo->q_scale_factor[0], force_baseline);
1.107 + jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,
1.108 + cinfo->q_scale_factor[1], force_baseline);
1.109 +}
1.110 +#endif
1.111 +
1.112 +
1.113 +GLOBAL(void)
1.114 +jpeg_set_linear_quality (j_compress_ptr cinfo, int scale_factor,
1.115 + boolean force_baseline)
1.116 +/* Set or change the 'quality' (quantization) setting, using default tables
1.117 + * and a straight percentage-scaling quality scale. In most cases it's better
1.118 + * to use jpeg_set_quality (below); this entry point is provided for
1.119 + * applications that insist on a linear percentage scaling.
1.120 + */
1.121 +{
1.122 + /* Set up two quantization tables using the specified scaling */
1.123 + jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl,
1.124 + scale_factor, force_baseline);
1.125 + jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl,
1.126 + scale_factor, force_baseline);
1.127 +}
1.128 +
1.129 +
1.130 +GLOBAL(int)
1.131 +jpeg_quality_scaling (int quality)
1.132 +/* Convert a user-specified quality rating to a percentage scaling factor
1.133 + * for an underlying quantization table, using our recommended scaling curve.
1.134 + * The input 'quality' factor should be 0 (terrible) to 100 (very good).
1.135 + */
1.136 +{
1.137 + /* Safety limit on quality factor. Convert 0 to 1 to avoid zero divide. */
1.138 + if (quality <= 0) quality = 1;
1.139 + if (quality > 100) quality = 100;
1.140 +
1.141 + /* The basic table is used as-is (scaling 100) for a quality of 50.
1.142 + * Qualities 50..100 are converted to scaling percentage 200 - 2*Q;
1.143 + * note that at Q=100 the scaling is 0, which will cause jpeg_add_quant_table
1.144 + * to make all the table entries 1 (hence, minimum quantization loss).
1.145 + * Qualities 1..50 are converted to scaling percentage 5000/Q.
1.146 + */
1.147 + if (quality < 50)
1.148 + quality = 5000 / quality;
1.149 + else
1.150 + quality = 200 - quality*2;
1.151 +
1.152 + return quality;
1.153 +}
1.154 +
1.155 +
1.156 +GLOBAL(void)
1.157 +jpeg_set_quality (j_compress_ptr cinfo, int quality, boolean force_baseline)
1.158 +/* Set or change the 'quality' (quantization) setting, using default tables.
1.159 + * This is the standard quality-adjusting entry point for typical user
1.160 + * interfaces; only those who want detailed control over quantization tables
1.161 + * would use the preceding three routines directly.
1.162 + */
1.163 +{
1.164 + /* Convert user 0-100 rating to percentage scaling */
1.165 + quality = jpeg_quality_scaling(quality);
1.166 +
1.167 + /* Set up standard quality tables */
1.168 + jpeg_set_linear_quality(cinfo, quality, force_baseline);
1.169 +}
1.170 +
1.171 +
1.172 +/*
1.173 + * Default parameter setup for compression.
1.174 + *
1.175 + * Applications that don't choose to use this routine must do their
1.176 + * own setup of all these parameters. Alternately, you can call this
1.177 + * to establish defaults and then alter parameters selectively. This
1.178 + * is the recommended approach since, if we add any new parameters,
1.179 + * your code will still work (they'll be set to reasonable defaults).
1.180 + */
1.181 +
1.182 +GLOBAL(void)
1.183 +jpeg_set_defaults (j_compress_ptr cinfo)
1.184 +{
1.185 + int i;
1.186 +
1.187 + /* Safety check to ensure start_compress not called yet. */
1.188 + if (cinfo->global_state != CSTATE_START)
1.189 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
1.190 +
1.191 + /* Allocate comp_info array large enough for maximum component count.
1.192 + * Array is made permanent in case application wants to compress
1.193 + * multiple images at same param settings.
1.194 + */
1.195 + if (cinfo->comp_info == NULL)
1.196 + cinfo->comp_info = (jpeg_component_info *)
1.197 + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
1.198 + MAX_COMPONENTS * SIZEOF(jpeg_component_info));
1.199 +
1.200 + /* Initialize everything not dependent on the color space */
1.201 +
1.202 +#if JPEG_LIB_VERSION >= 70
1.203 + cinfo->scale_num = 1; /* 1:1 scaling */
1.204 + cinfo->scale_denom = 1;
1.205 +#endif
1.206 + cinfo->data_precision = BITS_IN_JSAMPLE;
1.207 + /* Set up two quantization tables using default quality of 75 */
1.208 + jpeg_set_quality(cinfo, 75, TRUE);
1.209 + /* Set up two Huffman tables */
1.210 + std_huff_tables((j_common_ptr) cinfo);
1.211 +
1.212 + /* Initialize default arithmetic coding conditioning */
1.213 + for (i = 0; i < NUM_ARITH_TBLS; i++) {
1.214 + cinfo->arith_dc_L[i] = 0;
1.215 + cinfo->arith_dc_U[i] = 1;
1.216 + cinfo->arith_ac_K[i] = 5;
1.217 + }
1.218 +
1.219 + /* Default is no multiple-scan output */
1.220 + cinfo->scan_info = NULL;
1.221 + cinfo->num_scans = 0;
1.222 +
1.223 + /* Expect normal source image, not raw downsampled data */
1.224 + cinfo->raw_data_in = FALSE;
1.225 +
1.226 + /* Use Huffman coding, not arithmetic coding, by default */
1.227 + cinfo->arith_code = FALSE;
1.228 +
1.229 + /* By default, don't do extra passes to optimize entropy coding */
1.230 + cinfo->optimize_coding = FALSE;
1.231 + /* The standard Huffman tables are only valid for 8-bit data precision.
1.232 + * If the precision is higher, force optimization on so that usable
1.233 + * tables will be computed. This test can be removed if default tables
1.234 + * are supplied that are valid for the desired precision.
1.235 + */
1.236 + if (cinfo->data_precision > 8)
1.237 + cinfo->optimize_coding = TRUE;
1.238 +
1.239 + /* By default, use the simpler non-cosited sampling alignment */
1.240 + cinfo->CCIR601_sampling = FALSE;
1.241 +
1.242 +#if JPEG_LIB_VERSION >= 70
1.243 + /* By default, apply fancy downsampling */
1.244 + cinfo->do_fancy_downsampling = TRUE;
1.245 +#endif
1.246 +
1.247 + /* No input smoothing */
1.248 + cinfo->smoothing_factor = 0;
1.249 +
1.250 + /* DCT algorithm preference */
1.251 + cinfo->dct_method = JDCT_DEFAULT;
1.252 +
1.253 + /* No restart markers */
1.254 + cinfo->restart_interval = 0;
1.255 + cinfo->restart_in_rows = 0;
1.256 +
1.257 + /* Fill in default JFIF marker parameters. Note that whether the marker
1.258 + * will actually be written is determined by jpeg_set_colorspace.
1.259 + *
1.260 + * By default, the library emits JFIF version code 1.01.
1.261 + * An application that wants to emit JFIF 1.02 extension markers should set
1.262 + * JFIF_minor_version to 2. We could probably get away with just defaulting
1.263 + * to 1.02, but there may still be some decoders in use that will complain
1.264 + * about that; saying 1.01 should minimize compatibility problems.
1.265 + */
1.266 + cinfo->JFIF_major_version = 1; /* Default JFIF version = 1.01 */
1.267 + cinfo->JFIF_minor_version = 1;
1.268 + cinfo->density_unit = 0; /* Pixel size is unknown by default */
1.269 + cinfo->X_density = 1; /* Pixel aspect ratio is square by default */
1.270 + cinfo->Y_density = 1;
1.271 +
1.272 + /* Choose JPEG colorspace based on input space, set defaults accordingly */
1.273 +
1.274 + jpeg_default_colorspace(cinfo);
1.275 +}
1.276 +
1.277 +
1.278 +/*
1.279 + * Select an appropriate JPEG colorspace for in_color_space.
1.280 + */
1.281 +
1.282 +GLOBAL(void)
1.283 +jpeg_default_colorspace (j_compress_ptr cinfo)
1.284 +{
1.285 + switch (cinfo->in_color_space) {
1.286 + case JCS_GRAYSCALE:
1.287 + jpeg_set_colorspace(cinfo, JCS_GRAYSCALE);
1.288 + break;
1.289 + case JCS_RGB:
1.290 + case JCS_EXT_RGB:
1.291 + case JCS_EXT_RGBX:
1.292 + case JCS_EXT_BGR:
1.293 + case JCS_EXT_BGRX:
1.294 + case JCS_EXT_XBGR:
1.295 + case JCS_EXT_XRGB:
1.296 + case JCS_EXT_RGBA:
1.297 + case JCS_EXT_BGRA:
1.298 + case JCS_EXT_ABGR:
1.299 + case JCS_EXT_ARGB:
1.300 + jpeg_set_colorspace(cinfo, JCS_YCbCr);
1.301 + break;
1.302 + case JCS_YCbCr:
1.303 + jpeg_set_colorspace(cinfo, JCS_YCbCr);
1.304 + break;
1.305 + case JCS_CMYK:
1.306 + jpeg_set_colorspace(cinfo, JCS_CMYK); /* By default, no translation */
1.307 + break;
1.308 + case JCS_YCCK:
1.309 + jpeg_set_colorspace(cinfo, JCS_YCCK);
1.310 + break;
1.311 + case JCS_UNKNOWN:
1.312 + jpeg_set_colorspace(cinfo, JCS_UNKNOWN);
1.313 + break;
1.314 + default:
1.315 + ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
1.316 + }
1.317 +}
1.318 +
1.319 +
1.320 +/*
1.321 + * Set the JPEG colorspace, and choose colorspace-dependent default values.
1.322 + */
1.323 +
1.324 +GLOBAL(void)
1.325 +jpeg_set_colorspace (j_compress_ptr cinfo, J_COLOR_SPACE colorspace)
1.326 +{
1.327 + jpeg_component_info * compptr;
1.328 + int ci;
1.329 +
1.330 +#define SET_COMP(index,id,hsamp,vsamp,quant,dctbl,actbl) \
1.331 + (compptr = &cinfo->comp_info[index], \
1.332 + compptr->component_id = (id), \
1.333 + compptr->h_samp_factor = (hsamp), \
1.334 + compptr->v_samp_factor = (vsamp), \
1.335 + compptr->quant_tbl_no = (quant), \
1.336 + compptr->dc_tbl_no = (dctbl), \
1.337 + compptr->ac_tbl_no = (actbl) )
1.338 +
1.339 + /* Safety check to ensure start_compress not called yet. */
1.340 + if (cinfo->global_state != CSTATE_START)
1.341 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
1.342 +
1.343 + /* For all colorspaces, we use Q and Huff tables 0 for luminance components,
1.344 + * tables 1 for chrominance components.
1.345 + */
1.346 +
1.347 + cinfo->jpeg_color_space = colorspace;
1.348 +
1.349 + cinfo->write_JFIF_header = FALSE; /* No marker for non-JFIF colorspaces */
1.350 + cinfo->write_Adobe_marker = FALSE; /* write no Adobe marker by default */
1.351 +
1.352 + switch (colorspace) {
1.353 + case JCS_GRAYSCALE:
1.354 + cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */
1.355 + cinfo->num_components = 1;
1.356 + /* JFIF specifies component ID 1 */
1.357 + SET_COMP(0, 1, 1,1, 0, 0,0);
1.358 + break;
1.359 + case JCS_RGB:
1.360 + cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag RGB */
1.361 + cinfo->num_components = 3;
1.362 + SET_COMP(0, 0x52 /* 'R' */, 1,1, 0, 0,0);
1.363 + SET_COMP(1, 0x47 /* 'G' */, 1,1, 0, 0,0);
1.364 + SET_COMP(2, 0x42 /* 'B' */, 1,1, 0, 0,0);
1.365 + break;
1.366 + case JCS_YCbCr:
1.367 + cinfo->write_JFIF_header = TRUE; /* Write a JFIF marker */
1.368 + cinfo->num_components = 3;
1.369 + /* JFIF specifies component IDs 1,2,3 */
1.370 + /* We default to 2x2 subsamples of chrominance */
1.371 + SET_COMP(0, 1, 2,2, 0, 0,0);
1.372 + SET_COMP(1, 2, 1,1, 1, 1,1);
1.373 + SET_COMP(2, 3, 1,1, 1, 1,1);
1.374 + break;
1.375 + case JCS_CMYK:
1.376 + cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag CMYK */
1.377 + cinfo->num_components = 4;
1.378 + SET_COMP(0, 0x43 /* 'C' */, 1,1, 0, 0,0);
1.379 + SET_COMP(1, 0x4D /* 'M' */, 1,1, 0, 0,0);
1.380 + SET_COMP(2, 0x59 /* 'Y' */, 1,1, 0, 0,0);
1.381 + SET_COMP(3, 0x4B /* 'K' */, 1,1, 0, 0,0);
1.382 + break;
1.383 + case JCS_YCCK:
1.384 + cinfo->write_Adobe_marker = TRUE; /* write Adobe marker to flag YCCK */
1.385 + cinfo->num_components = 4;
1.386 + SET_COMP(0, 1, 2,2, 0, 0,0);
1.387 + SET_COMP(1, 2, 1,1, 1, 1,1);
1.388 + SET_COMP(2, 3, 1,1, 1, 1,1);
1.389 + SET_COMP(3, 4, 2,2, 0, 0,0);
1.390 + break;
1.391 + case JCS_UNKNOWN:
1.392 + cinfo->num_components = cinfo->input_components;
1.393 + if (cinfo->num_components < 1 || cinfo->num_components > MAX_COMPONENTS)
1.394 + ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
1.395 + MAX_COMPONENTS);
1.396 + for (ci = 0; ci < cinfo->num_components; ci++) {
1.397 + SET_COMP(ci, ci, 1,1, 0, 0,0);
1.398 + }
1.399 + break;
1.400 + default:
1.401 + ERREXIT(cinfo, JERR_BAD_J_COLORSPACE);
1.402 + }
1.403 +}
1.404 +
1.405 +
1.406 +#ifdef C_PROGRESSIVE_SUPPORTED
1.407 +
1.408 +LOCAL(jpeg_scan_info *)
1.409 +fill_a_scan (jpeg_scan_info * scanptr, int ci,
1.410 + int Ss, int Se, int Ah, int Al)
1.411 +/* Support routine: generate one scan for specified component */
1.412 +{
1.413 + scanptr->comps_in_scan = 1;
1.414 + scanptr->component_index[0] = ci;
1.415 + scanptr->Ss = Ss;
1.416 + scanptr->Se = Se;
1.417 + scanptr->Ah = Ah;
1.418 + scanptr->Al = Al;
1.419 + scanptr++;
1.420 + return scanptr;
1.421 +}
1.422 +
1.423 +LOCAL(jpeg_scan_info *)
1.424 +fill_scans (jpeg_scan_info * scanptr, int ncomps,
1.425 + int Ss, int Se, int Ah, int Al)
1.426 +/* Support routine: generate one scan for each component */
1.427 +{
1.428 + int ci;
1.429 +
1.430 + for (ci = 0; ci < ncomps; ci++) {
1.431 + scanptr->comps_in_scan = 1;
1.432 + scanptr->component_index[0] = ci;
1.433 + scanptr->Ss = Ss;
1.434 + scanptr->Se = Se;
1.435 + scanptr->Ah = Ah;
1.436 + scanptr->Al = Al;
1.437 + scanptr++;
1.438 + }
1.439 + return scanptr;
1.440 +}
1.441 +
1.442 +LOCAL(jpeg_scan_info *)
1.443 +fill_dc_scans (jpeg_scan_info * scanptr, int ncomps, int Ah, int Al)
1.444 +/* Support routine: generate interleaved DC scan if possible, else N scans */
1.445 +{
1.446 + int ci;
1.447 +
1.448 + if (ncomps <= MAX_COMPS_IN_SCAN) {
1.449 + /* Single interleaved DC scan */
1.450 + scanptr->comps_in_scan = ncomps;
1.451 + for (ci = 0; ci < ncomps; ci++)
1.452 + scanptr->component_index[ci] = ci;
1.453 + scanptr->Ss = scanptr->Se = 0;
1.454 + scanptr->Ah = Ah;
1.455 + scanptr->Al = Al;
1.456 + scanptr++;
1.457 + } else {
1.458 + /* Noninterleaved DC scan for each component */
1.459 + scanptr = fill_scans(scanptr, ncomps, 0, 0, Ah, Al);
1.460 + }
1.461 + return scanptr;
1.462 +}
1.463 +
1.464 +
1.465 +/*
1.466 + * Create a recommended progressive-JPEG script.
1.467 + * cinfo->num_components and cinfo->jpeg_color_space must be correct.
1.468 + */
1.469 +
1.470 +GLOBAL(void)
1.471 +jpeg_simple_progression (j_compress_ptr cinfo)
1.472 +{
1.473 + int ncomps = cinfo->num_components;
1.474 + int nscans;
1.475 + jpeg_scan_info * scanptr;
1.476 +
1.477 + /* Safety check to ensure start_compress not called yet. */
1.478 + if (cinfo->global_state != CSTATE_START)
1.479 + ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
1.480 +
1.481 + /* Figure space needed for script. Calculation must match code below! */
1.482 + if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
1.483 + /* Custom script for YCbCr color images. */
1.484 + nscans = 10;
1.485 + } else {
1.486 + /* All-purpose script for other color spaces. */
1.487 + if (ncomps > MAX_COMPS_IN_SCAN)
1.488 + nscans = 6 * ncomps; /* 2 DC + 4 AC scans per component */
1.489 + else
1.490 + nscans = 2 + 4 * ncomps; /* 2 DC scans; 4 AC scans per component */
1.491 + }
1.492 +
1.493 + /* Allocate space for script.
1.494 + * We need to put it in the permanent pool in case the application performs
1.495 + * multiple compressions without changing the settings. To avoid a memory
1.496 + * leak if jpeg_simple_progression is called repeatedly for the same JPEG
1.497 + * object, we try to re-use previously allocated space, and we allocate
1.498 + * enough space to handle YCbCr even if initially asked for grayscale.
1.499 + */
1.500 + if (cinfo->script_space == NULL || cinfo->script_space_size < nscans) {
1.501 + cinfo->script_space_size = MAX(nscans, 10);
1.502 + cinfo->script_space = (jpeg_scan_info *)
1.503 + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
1.504 + cinfo->script_space_size * SIZEOF(jpeg_scan_info));
1.505 + }
1.506 + scanptr = cinfo->script_space;
1.507 + cinfo->scan_info = scanptr;
1.508 + cinfo->num_scans = nscans;
1.509 +
1.510 + if (ncomps == 3 && cinfo->jpeg_color_space == JCS_YCbCr) {
1.511 + /* Custom script for YCbCr color images. */
1.512 + /* Initial DC scan */
1.513 + scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
1.514 + /* Initial AC scan: get some luma data out in a hurry */
1.515 + scanptr = fill_a_scan(scanptr, 0, 1, 5, 0, 2);
1.516 + /* Chroma data is too small to be worth expending many scans on */
1.517 + scanptr = fill_a_scan(scanptr, 2, 1, 63, 0, 1);
1.518 + scanptr = fill_a_scan(scanptr, 1, 1, 63, 0, 1);
1.519 + /* Complete spectral selection for luma AC */
1.520 + scanptr = fill_a_scan(scanptr, 0, 6, 63, 0, 2);
1.521 + /* Refine next bit of luma AC */
1.522 + scanptr = fill_a_scan(scanptr, 0, 1, 63, 2, 1);
1.523 + /* Finish DC successive approximation */
1.524 + scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
1.525 + /* Finish AC successive approximation */
1.526 + scanptr = fill_a_scan(scanptr, 2, 1, 63, 1, 0);
1.527 + scanptr = fill_a_scan(scanptr, 1, 1, 63, 1, 0);
1.528 + /* Luma bottom bit comes last since it's usually largest scan */
1.529 + scanptr = fill_a_scan(scanptr, 0, 1, 63, 1, 0);
1.530 + } else {
1.531 + /* All-purpose script for other color spaces. */
1.532 + /* Successive approximation first pass */
1.533 + scanptr = fill_dc_scans(scanptr, ncomps, 0, 1);
1.534 + scanptr = fill_scans(scanptr, ncomps, 1, 5, 0, 2);
1.535 + scanptr = fill_scans(scanptr, ncomps, 6, 63, 0, 2);
1.536 + /* Successive approximation second pass */
1.537 + scanptr = fill_scans(scanptr, ncomps, 1, 63, 2, 1);
1.538 + /* Successive approximation final pass */
1.539 + scanptr = fill_dc_scans(scanptr, ncomps, 1, 0);
1.540 + scanptr = fill_scans(scanptr, ncomps, 1, 63, 1, 0);
1.541 + }
1.542 +}
1.543 +
1.544 +#endif /* C_PROGRESSIVE_SUPPORTED */
