jpeg.c

   1 /*
   2         Copyright (C) 2002  Mathieu Olivier
   3
   4         This program is free software; you can redistribute it and/or
   5         modify it under the terms of the GNU General Public License
   6         as published by the Free Software Foundation; either version 2
   7         of the License, or (at your option) any later version.
   8
   9         This program is distributed in the hope that it will be useful,
  10         but WITHOUT ANY WARRANTY; without even the implied warranty of
  11         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  12
  13         See the GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to:
  17
  18                 Free Software Foundation, Inc.
  19                 59 Temple Place - Suite 330
  20                 Boston, MA  02111-1307, USA
  21
  22 */
  23
  24
  25 #include "quakedef.h"
  26 #include "image.h"
  27 #include "jpeg.h"
  28
  29 cvar_t sv_writepicture_quality = {CVAR_SAVE, "sv_writepicture_quality", "10", "WritePicture quality offset (higher means better quality, but slower)"};
  30
  31 // jboolean is unsigned char instead of int on Win32
  32 #ifdef WIN32
  33 typedef unsigned char jboolean;
  34 #else
  35 typedef int jboolean;
  36 #endif
  37
  38 #ifdef LINK_TO_LIBJPEG
  39 #include <jpeglib.h>
  40 #define qjpeg_create_compress jpeg_create_compress
  41 #define qjpeg_create_decompress jpeg_create_decompress
  42 #define qjpeg_destroy_compress jpeg_destroy_compress
  43 #define qjpeg_destroy_decompress jpeg_destroy_decompress
  44 #define qjpeg_finish_compress jpeg_finish_compress
  45 #define qjpeg_finish_decompress jpeg_finish_decompress
  46 #define qjpeg_resync_to_restart jpeg_resync_to_restart
  47 #define qjpeg_read_header jpeg_read_header
  48 #define qjpeg_read_scanlines jpeg_read_scanlines
  49 #define qjpeg_set_defaults jpeg_set_defaults
  50 #define qjpeg_set_quality jpeg_set_quality
  51 #define qjpeg_start_compress jpeg_start_compress
  52 #define qjpeg_start_decompress jpeg_start_decompress
  53 #define qjpeg_std_error jpeg_std_error
  54 #define qjpeg_write_scanlines jpeg_write_scanlines
  55 #define jpeg_dll true
  56 #else
  57 /*
  58 =================================================================
  59
  60   Minimal set of definitions from the JPEG lib
  61
  62   WARNING: for a matter of simplicity, several pointer types are
  63   casted to "void*", and most enumerated values are not included
  64
  65 =================================================================
  66 */
  67
  68 typedef void *j_common_ptr;
  69 typedef struct jpeg_compress_struct *j_compress_ptr;
  70 typedef struct jpeg_decompress_struct *j_decompress_ptr;
  71
  72 #define JPEG_LIB_VERSION  62  // Version 6b
  73
  74 typedef enum
  75 {
  76         JCS_UNKNOWN,
  77         JCS_GRAYSCALE,
  78         JCS_RGB,
  79         JCS_YCbCr,
  80         JCS_CMYK,
  81         JCS_YCCK
  82 } J_COLOR_SPACE;
  83 typedef enum {JPEG_DUMMY1} J_DCT_METHOD;
  84 typedef enum {JPEG_DUMMY2} J_DITHER_MODE;
  85 typedef unsigned int JDIMENSION;
  86
  87 #define JPOOL_PERMANENT 0       // lasts until master record is destroyed
  88 #define JPOOL_IMAGE             1       // lasts until done with image/datastream
  89
  90 #define JPEG_EOI        0xD9  // EOI marker code
  91
  92 #define JMSG_STR_PARM_MAX  80
  93
  94 #define DCTSIZE2 64
  95 #define NUM_QUANT_TBLS 4
  96 #define NUM_HUFF_TBLS 4
  97 #define NUM_ARITH_TBLS 16
  98 #define MAX_COMPS_IN_SCAN 4
  99 #define C_MAX_BLOCKS_IN_MCU 10
 100 #define D_MAX_BLOCKS_IN_MCU 10
 101
 102 struct jpeg_memory_mgr
 103 {
 104   void* (*alloc_small) (j_common_ptr cinfo, int pool_id, size_t sizeofobject);
 105   void (*_reserve_space_for_alloc_large) (void *dummy, ...);
 106   void (*_reserve_space_for_alloc_sarray) (void *dummy, ...);
 107   void (*_reserve_space_for_alloc_barray) (void *dummy, ...);
 108   void (*_reserve_space_for_request_virt_sarray) (void *dummy, ...);
 109   void (*_reserve_space_for_request_virt_barray) (void *dummy, ...);
 110   void (*_reserve_space_for_realize_virt_arrays) (void *dummy, ...);
 111   void (*_reserve_space_for_access_virt_sarray) (void *dummy, ...);
 112   void (*_reserve_space_for_access_virt_barray) (void *dummy, ...);
 113   void (*_reserve_space_for_free_pool) (void *dummy, ...);
 114   void (*_reserve_space_for_self_destruct) (void *dummy, ...);
 115
 116   long max_memory_to_use;
 117   long max_alloc_chunk;
 118 };
 119
 120 struct jpeg_error_mgr
 121 {
 122         void (*error_exit) (j_common_ptr cinfo);
 123         void (*emit_message) (j_common_ptr cinfo, int msg_level);
 124         void (*output_message) (j_common_ptr cinfo);
 125         void (*format_message) (j_common_ptr cinfo, char * buffer);
 126         void (*reset_error_mgr) (j_common_ptr cinfo);
 127         int msg_code;
 128         union {
 129                 int i[8];
 130                 char s[JMSG_STR_PARM_MAX];
 131         } msg_parm;
 132         int trace_level;
 133         long num_warnings;
 134         const char * const * jpeg_message_table;
 135         int last_jpeg_message;
 136         const char * const * addon_message_table;
 137         int first_addon_message;
 138         int last_addon_message;
 139 };
 140
 141 struct jpeg_source_mgr
 142 {
 143         const unsigned char *next_input_byte;
 144         size_t bytes_in_buffer;
 145
 146         void (*init_source) (j_decompress_ptr cinfo);
 147         jboolean (*fill_input_buffer) (j_decompress_ptr cinfo);
 148         void (*skip_input_data) (j_decompress_ptr cinfo, long num_bytes);
 149         jboolean (*resync_to_restart) (j_decompress_ptr cinfo, int desired);
 150         void (*term_source) (j_decompress_ptr cinfo);
 151 };
 152
 153 typedef struct {
 154   /* These values are fixed over the whole image. */
 155   /* For compression, they must be supplied by parameter setup; */
 156   /* for decompression, they are read from the SOF marker. */
 157   int component_id;             /* identifier for this component (0..255) */
 158   int component_index;          /* its index in SOF or cinfo->comp_info[] */
 159   int h_samp_factor;            /* horizontal sampling factor (1..4) */
 160   int v_samp_factor;            /* vertical sampling factor (1..4) */
 161   int quant_tbl_no;             /* quantization table selector (0..3) */
 162   /* These values may vary between scans. */
 163   /* For compression, they must be supplied by parameter setup; */
 164   /* for decompression, they are read from the SOS marker. */
 165   /* The decompressor output side may not use these variables. */
 166   int dc_tbl_no;                /* DC entropy table selector (0..3) */
 167   int ac_tbl_no;                /* AC entropy table selector (0..3) */
 168
 169   /* Remaining fields should be treated as private by applications. */
 170
 171   /* These values are computed during compression or decompression startup: */
 172   /* Component's size in DCT blocks.
 173    * Any dummy blocks added to complete an MCU are not counted; therefore
 174    * these values do not depend on whether a scan is interleaved or not.
 175    */
 176   JDIMENSION width_in_blocks;
 177   JDIMENSION height_in_blocks;
 178   /* Size of a DCT block in samples.  Always DCTSIZE for compression.
 179    * For decompression this is the size of the output from one DCT block,
 180    * reflecting any scaling we choose to apply during the IDCT step.
 181    * Values of 1,2,4,8 are likely to be supported.  Note that different
 182    * components may receive different IDCT scalings.
 183    */
 184   int DCT_scaled_size;
 185   /* The downsampled dimensions are the component's actual, unpadded number
 186    * of samples at the main buffer (preprocessing/compression interface), thus
 187    * downsampled_width = ceil(image_width * Hi/Hmax)
 188    * and similarly for height.  For decompression, IDCT scaling is included, so
 189    * downsampled_width = ceil(image_width * Hi/Hmax * DCT_scaled_size/DCTSIZE)
 190    */
 191   JDIMENSION downsampled_width;  /* actual width in samples */
 192   JDIMENSION downsampled_height; /* actual height in samples */
 193   /* This flag is used only for decompression.  In cases where some of the
 194    * components will be ignored (eg grayscale output from YCbCr image),
 195    * we can skip most computations for the unused components.
 196    */
 197   jboolean component_needed;     /* do we need the value of this component? */
 198
 199   /* These values are computed before starting a scan of the component. */
 200   /* The decompressor output side may not use these variables. */
 201   int MCU_width;                /* number of blocks per MCU, horizontally */
 202   int MCU_height;               /* number of blocks per MCU, vertically */
 203   int MCU_blocks;               /* MCU_width * MCU_height */
 204   int MCU_sample_width;         /* MCU width in samples, MCU_width*DCT_scaled_size */
 205   int last_col_width;           /* # of non-dummy blocks across in last MCU */
 206   int last_row_height;          /* # of non-dummy blocks down in last MCU */
 207
 208   /* Saved quantization table for component; NULL if none yet saved.
 209    * See jdinput.c comments about the need for this information.
 210    * This field is currently used only for decompression.
 211    */
 212   void *quant_table;
 213
 214   /* Private per-component storage for DCT or IDCT subsystem. */
 215   void * dct_table;
 216 } jpeg_component_info;
 217
 218 struct jpeg_decompress_struct
 219 {
 220         struct jpeg_error_mgr *err;             // USED
 221         struct jpeg_memory_mgr *mem;    // USED
 222
 223         void *progress;
 224         void *client_data;
 225         jboolean is_decompressor;
 226         int global_state;
 227
 228         struct jpeg_source_mgr *src;    // USED
 229         JDIMENSION image_width;                 // USED
 230         JDIMENSION image_height;                // USED
 231
 232         int num_components;
 233         J_COLOR_SPACE jpeg_color_space;
 234         J_COLOR_SPACE out_color_space;
 235         unsigned int scale_num, scale_denom;
 236         double output_gamma;
 237         jboolean buffered_image;
 238         jboolean raw_data_out;
 239         J_DCT_METHOD dct_method;
 240         jboolean do_fancy_upsampling;
 241         jboolean do_block_smoothing;
 242         jboolean quantize_colors;
 243         J_DITHER_MODE dither_mode;
 244         jboolean two_pass_quantize;
 245         int desired_number_of_colors;
 246         jboolean enable_1pass_quant;
 247         jboolean enable_external_quant;
 248         jboolean enable_2pass_quant;
 249         JDIMENSION output_width;
 250
 251         JDIMENSION output_height;       // USED
 252
 253         int out_color_components;
 254
 255         int output_components;          // USED
 256
 257         int rec_outbuf_height;
 258         int actual_number_of_colors;
 259         void *colormap;
 260
 261         JDIMENSION output_scanline;     // USED
 262
 263         int input_scan_number;
 264         JDIMENSION input_iMCU_row;
 265         int output_scan_number;
 266         JDIMENSION output_iMCU_row;
 267         int (*coef_bits)[DCTSIZE2];
 268         void *quant_tbl_ptrs[NUM_QUANT_TBLS];
 269         void *dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
 270         void *ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
 271         int data_precision;
 272         jpeg_component_info *comp_info;
 273         jboolean progressive_mode;
 274         jboolean arith_code;
 275         unsigned char arith_dc_L[NUM_ARITH_TBLS];
 276         unsigned char arith_dc_U[NUM_ARITH_TBLS];
 277         unsigned char arith_ac_K[NUM_ARITH_TBLS];
 278         unsigned int restart_interval;
 279         jboolean saw_JFIF_marker;
 280         unsigned char JFIF_major_version;
 281         unsigned char JFIF_minor_version;
 282         unsigned char density_unit;
 283         unsigned short X_density;
 284         unsigned short Y_density;
 285         jboolean saw_Adobe_marker;
 286         unsigned char Adobe_transform;
 287         jboolean CCIR601_sampling;
 288         void *marker_list;
 289         int max_h_samp_factor;
 290         int max_v_samp_factor;
 291         int min_DCT_scaled_size;
 292         JDIMENSION total_iMCU_rows;
 293         void *sample_range_limit;
 294         int comps_in_scan;
 295         jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN];
 296         JDIMENSION MCUs_per_row;
 297         JDIMENSION MCU_rows_in_scan;
 298         int blocks_in_MCU;
 299         int MCU_membership[D_MAX_BLOCKS_IN_MCU];
 300         int Ss, Se, Ah, Al;
 301         int unread_marker;
 302         void *master;
 303         void *main;
 304         void *coef;
 305         void *post;
 306         void *inputctl;
 307         void *marker;
 308         void *entropy;
 309         void *idct;
 310         void *upsample;
 311         void *cconvert;
 312         void *cquantize;
 313 };
 314
 315
 316 struct jpeg_compress_struct
 317 {
 318         struct jpeg_error_mgr *err;
 319         struct jpeg_memory_mgr *mem;
 320         void *progress;
 321         void *client_data;
 322         jboolean is_decompressor;
 323         int global_state;
 324
 325         void *dest;
 326         JDIMENSION image_width;
 327         JDIMENSION image_height;
 328         int input_components;
 329         J_COLOR_SPACE in_color_space;
 330         double input_gamma;
 331         int data_precision;
 332
 333         int num_components;
 334         J_COLOR_SPACE jpeg_color_space;
 335         jpeg_component_info *comp_info;
 336         void *quant_tbl_ptrs[NUM_QUANT_TBLS];
 337         void *dc_huff_tbl_ptrs[NUM_HUFF_TBLS];
 338         void *ac_huff_tbl_ptrs[NUM_HUFF_TBLS];
 339         unsigned char arith_dc_L[NUM_ARITH_TBLS];
 340         unsigned char arith_dc_U[NUM_ARITH_TBLS];
 341         unsigned char arith_ac_K[NUM_ARITH_TBLS];
 342
 343         int num_scans;
 344         const void *scan_info;
 345         jboolean raw_data_in;
 346         jboolean arith_code;
 347         jboolean optimize_coding;
 348         jboolean CCIR601_sampling;
 349         int smoothing_factor;
 350         J_DCT_METHOD dct_method;
 351
 352         unsigned int restart_interval;
 353         int restart_in_rows;
 354
 355         jboolean write_JFIF_header;
 356         unsigned char JFIF_major_version;
 357         unsigned char JFIF_minor_version;
 358         unsigned char density_unit;
 359         unsigned short X_density;
 360         unsigned short Y_density;
 361         jboolean write_Adobe_marker;
 362         JDIMENSION next_scanline;
 363
 364         jboolean progressive_mode;
 365         int max_h_samp_factor;
 366         int max_v_samp_factor;
 367         JDIMENSION total_iMCU_rows;
 368         int comps_in_scan;
 369         jpeg_component_info *cur_comp_info[MAX_COMPS_IN_SCAN];
 370         JDIMENSION MCUs_per_row;
 371         JDIMENSION MCU_rows_in_scan;
 372         int blocks_in_MCU;
 373         int MCU_membership[C_MAX_BLOCKS_IN_MCU];
 374         int Ss, Se, Ah, Al;
 375
 376         void *master;
 377         void *main;
 378         void *prep;
 379         void *coef;
 380         void *marker;
 381         void *cconvert;
 382         void *downsample;
 383         void *fdct;
 384         void *entropy;
 385         void *script_space;
 386         int script_space_size;
 387 };
 388
 389 struct jpeg_destination_mgr
 390 {
 391         unsigned char* next_output_byte;
 392         size_t free_in_buffer;
 393
 394         void (*init_destination) (j_compress_ptr cinfo);
 395         jboolean (*empty_output_buffer) (j_compress_ptr cinfo);
 396         void (*term_destination) (j_compress_ptr cinfo);
 397 };
 398
 399
 400 /*
 401 =================================================================
 402
 403   DarkPlaces definitions
 404
 405 =================================================================
 406 */
 407
 408 // Functions exported from libjpeg
 409 #define qjpeg_create_compress(cinfo) \
 410         qjpeg_CreateCompress((cinfo), JPEG_LIB_VERSION, (size_t) sizeof(struct jpeg_compress_struct))
 411 #define qjpeg_create_decompress(cinfo) \
 412         qjpeg_CreateDecompress((cinfo), JPEG_LIB_VERSION, (size_t) sizeof(struct jpeg_decompress_struct))
 413
 414 static void (*qjpeg_CreateCompress) (j_compress_ptr cinfo, int version, size_t structsize);
 415 static void (*qjpeg_CreateDecompress) (j_decompress_ptr cinfo, int version, size_t structsize);
 416 static void (*qjpeg_destroy_compress) (j_compress_ptr cinfo);
 417 static void (*qjpeg_destroy_decompress) (j_decompress_ptr cinfo);
 418 static void (*qjpeg_finish_compress) (j_compress_ptr cinfo);
 419 static jboolean (*qjpeg_finish_decompress) (j_decompress_ptr cinfo);
 420 static jboolean (*qjpeg_resync_to_restart) (j_decompress_ptr cinfo, int desired);
 421 static int (*qjpeg_read_header) (j_decompress_ptr cinfo, jboolean require_image);
 422 static JDIMENSION (*qjpeg_read_scanlines) (j_decompress_ptr cinfo, unsigned char** scanlines, JDIMENSION max_lines);
 423 static void (*qjpeg_set_defaults) (j_compress_ptr cinfo);
 424 static void (*qjpeg_set_quality) (j_compress_ptr cinfo, int quality, jboolean force_baseline);
 425 static jboolean (*qjpeg_start_compress) (j_compress_ptr cinfo, jboolean write_all_tables);
 426 static jboolean (*qjpeg_start_decompress) (j_decompress_ptr cinfo);
 427 static struct jpeg_error_mgr* (*qjpeg_std_error) (struct jpeg_error_mgr *err);
 428 static JDIMENSION (*qjpeg_write_scanlines) (j_compress_ptr cinfo, unsigned char** scanlines, JDIMENSION num_lines);
 429
 430 static dllfunction_t jpegfuncs[] =
 431 {
 432         {"jpeg_CreateCompress",         (void **) &qjpeg_CreateCompress},
 433         {"jpeg_CreateDecompress",       (void **) &qjpeg_CreateDecompress},
 434         {"jpeg_destroy_compress",       (void **) &qjpeg_destroy_compress},
 435         {"jpeg_destroy_decompress",     (void **) &qjpeg_destroy_decompress},
 436         {"jpeg_finish_compress",        (void **) &qjpeg_finish_compress},
 437         {"jpeg_finish_decompress",      (void **) &qjpeg_finish_decompress},
 438         {"jpeg_resync_to_restart",      (void **) &qjpeg_resync_to_restart},
 439         {"jpeg_read_header",            (void **) &qjpeg_read_header},
 440         {"jpeg_read_scanlines",         (void **) &qjpeg_read_scanlines},
 441         {"jpeg_set_defaults",           (void **) &qjpeg_set_defaults},
 442         {"jpeg_set_quality",            (void **) &qjpeg_set_quality},
 443         {"jpeg_start_compress",         (void **) &qjpeg_start_compress},
 444         {"jpeg_start_decompress",       (void **) &qjpeg_start_decompress},
 445         {"jpeg_std_error",                      (void **) &qjpeg_std_error},
 446         {"jpeg_write_scanlines",        (void **) &qjpeg_write_scanlines},
 447         {NULL, NULL}
 448 };
 449
 450 // Handle for JPEG DLL
 451 dllhandle_t jpeg_dll = NULL;
 452 qboolean jpeg_tried_loading = 0;
 453 #endif
 454
 455 static unsigned char jpeg_eoi_marker [2] = {0xFF, JPEG_EOI};
 456 static jmp_buf error_in_jpeg;
 457 static qboolean jpeg_toolarge;
 458
 459 // Our own output manager for JPEG compression
 460 typedef struct
 461 {
 462         struct jpeg_destination_mgr pub;
 463
 464         qfile_t* outfile;
 465         unsigned char* buffer;
 466         size_t bufsize; // used if outfile is NULL
 467 } my_destination_mgr;
 468 typedef my_destination_mgr* my_dest_ptr;
 469
 470
 471 /*
 472 =================================================================
 473
 474   DLL load & unload
 475
 476 =================================================================
 477 */
 478
 479 /*
 480 ====================
 481 JPEG_OpenLibrary
 482
 483 Try to load the JPEG DLL
 484 ====================
 485 */
 486 qboolean JPEG_OpenLibrary (void)
 487 {
 488 #ifdef LINK_TO_LIBJPEG
 489         return true;
 490 #else
 491         const char* dllnames [] =
 492         {
 493 #if defined(WIN64)
 494                 "libjpeg64.dll",
 495 #elif defined(WIN32)
 496                 "libjpeg.dll",
 497 #elif defined(MACOSX)
 498                 "libjpeg.62.dylib",
 499 #else
 500                 "libjpeg.so.62",
 501                 "libjpeg.so",
 502 #endif
 503                 NULL
 504         };
 505
 506         // Already loaded?
 507         if (jpeg_dll)
 508                 return true;
 509
 510         if (jpeg_tried_loading) // only try once
 511                 return false;
 512
 513         jpeg_tried_loading = true;
 514
 515         // Load the DLL
 516         return Sys_LoadLibrary (dllnames, &jpeg_dll, jpegfuncs);
 517 #endif
 518 }
 519
 520
 521 /*
 522 ====================
 523 JPEG_CloseLibrary
 524
 525 Unload the JPEG DLL
 526 ====================
 527 */
 528 void JPEG_CloseLibrary (void)
 529 {
 530 #ifndef LINK_TO_LIBJPEG
 531         Sys_UnloadLibrary (&jpeg_dll);
 532         jpeg_tried_loading = false; // allow retry
 533 #endif
 534 }
 535
 536
 537 /*
 538 =================================================================
 539
 540         JPEG decompression
 541
 542 =================================================================
 543 */
 544
 545 static void JPEG_Noop (j_decompress_ptr cinfo) {}
 546
 547 static jboolean JPEG_FillInputBuffer (j_decompress_ptr cinfo)
 548 {
 549     // Insert a fake EOI marker
 550     cinfo->src->next_input_byte = jpeg_eoi_marker;
 551     cinfo->src->bytes_in_buffer = 2;
 552
 553         return TRUE;
 554 }
 555
 556 static void JPEG_SkipInputData (j_decompress_ptr cinfo, long num_bytes)
 557 {
 558     if (cinfo->src->bytes_in_buffer <= (unsigned long)num_bytes)
 559         {
 560                 cinfo->src->bytes_in_buffer = 0;
 561                 return;
 562         }
 563
 564     cinfo->src->next_input_byte += num_bytes;
 565     cinfo->src->bytes_in_buffer -= num_bytes;
 566 }
 567
 568 static void JPEG_MemSrc (j_decompress_ptr cinfo, const unsigned char *buffer, size_t filesize)
 569 {
 570         cinfo->src = (struct jpeg_source_mgr *)cinfo->mem->alloc_small ((j_common_ptr) cinfo, JPOOL_PERMANENT, sizeof (struct jpeg_source_mgr));
 571
 572         cinfo->src->next_input_byte = buffer;
 573         cinfo->src->bytes_in_buffer = filesize;
 574
 575         cinfo->src->init_source = JPEG_Noop;
 576         cinfo->src->fill_input_buffer = JPEG_FillInputBuffer;
 577         cinfo->src->skip_input_data = JPEG_SkipInputData;
 578         cinfo->src->resync_to_restart = qjpeg_resync_to_restart; // use the default method
 579         cinfo->src->term_source = JPEG_Noop;
 580 }
 581
 582 static void JPEG_ErrorExit (j_common_ptr cinfo)
 583 {
 584         ((struct jpeg_decompress_struct*)cinfo)->err->output_message (cinfo);
 585         longjmp(error_in_jpeg, 1);
 586 }
 587
 588
 589 /*
 590 ====================
 591 JPEG_LoadImage
 592
 593 Load a JPEG image into a BGRA buffer
 594 ====================
 595 */
 596 unsigned char* JPEG_LoadImage_BGRA (const unsigned char *f, int filesize)
 597 {
 598         struct jpeg_decompress_struct cinfo;
 599         struct jpeg_error_mgr jerr;
 600         unsigned char *image_buffer = NULL, *scanline = NULL;
 601         unsigned int line;
 602
 603         // No DLL = no JPEGs
 604         if (!jpeg_dll)
 605                 return NULL;
 606
 607         cinfo.err = qjpeg_std_error (&jerr);
 608         qjpeg_create_decompress (&cinfo);
 609         if(setjmp(error_in_jpeg))
 610                 goto error_caught;
 611         cinfo.err = qjpeg_std_error (&jerr);
 612         cinfo.err->error_exit = JPEG_ErrorExit;
 613         JPEG_MemSrc (&cinfo, f, filesize);
 614         qjpeg_read_header (&cinfo, TRUE);
 615         qjpeg_start_decompress (&cinfo);
 616
 617         image_width = cinfo.image_width;
 618         image_height = cinfo.image_height;
 619
 620         if (image_width > 4096 || image_height > 4096 || image_width <= 0 || image_height <= 0)
 621         {
 622                 Con_Printf("JPEG_LoadImage: invalid image size %ix%i\n", image_width, image_height);
 623                 return NULL;
 624         }
 625
 626         image_buffer = (unsigned char *)Mem_Alloc(tempmempool, image_width * image_height * 4);
 627         scanline = (unsigned char *)Mem_Alloc(tempmempool, image_width * cinfo.output_components);
 628         if (!image_buffer || !scanline)
 629         {
 630                 if (image_buffer)
 631                         Mem_Free (image_buffer);
 632                 if (scanline)
 633                         Mem_Free (scanline);
 634
 635                 Con_Printf("JPEG_LoadImage: not enough memory for %i by %i image\n", image_width, image_height);
 636                 qjpeg_finish_decompress (&cinfo);
 637                 qjpeg_destroy_decompress (&cinfo);
 638                 return NULL;
 639         }
 640
 641         // Decompress the image, line by line
 642         line = 0;
 643         while (cinfo.output_scanline < cinfo.output_height)
 644         {
 645                 unsigned char *buffer_ptr;
 646                 int ind;
 647
 648                 qjpeg_read_scanlines (&cinfo, &scanline, 1);
 649
 650                 // Convert the image to BGRA
 651                 switch (cinfo.output_components)
 652                 {
 653                         // RGB images
 654                         case 3:
 655                                 buffer_ptr = &image_buffer[image_width * line * 4];
 656                                 for (ind = 0; ind < image_width * 3; ind += 3, buffer_ptr += 4)
 657                                 {
 658                                         buffer_ptr[2] = scanline[ind];
 659                                         buffer_ptr[1] = scanline[ind + 1];
 660                                         buffer_ptr[0] = scanline[ind + 2];
 661                                         buffer_ptr[3] = 255;
 662                                 }
 663                                 break;
 664
 665                         // Greyscale images (default to it, just in case)
 666                         case 1:
 667                         default:
 668                                 buffer_ptr = &image_buffer[image_width * line * 4];
 669                                 for (ind = 0; ind < image_width; ind++, buffer_ptr += 4)
 670                                 {
 671                                         buffer_ptr[0] = scanline[ind];
 672                                         buffer_ptr[1] = scanline[ind];
 673                                         buffer_ptr[2] = scanline[ind];
 674                                         buffer_ptr[3] = 255;
 675                                 }
 676                 }
 677
 678                 line++;
 679         }
 680         Mem_Free (scanline);
 681
 682         qjpeg_finish_decompress (&cinfo);
 683         qjpeg_destroy_decompress (&cinfo);
 684
 685         return image_buffer;
 686
 687 error_caught:
 688         if(scanline)
 689                 Mem_Free (scanline);
 690         if(image_buffer)
 691                 Mem_Free (image_buffer);
 692         qjpeg_destroy_decompress (&cinfo);
 693         return NULL;
 694 }
 695
 696
 697 /*
 698 =================================================================
 699
 700   JPEG compression
 701
 702 =================================================================
 703 */
 704
 705 #define JPEG_OUTPUT_BUF_SIZE 4096
 706 static void JPEG_InitDestination (j_compress_ptr cinfo)
 707 {
 708         my_dest_ptr dest = (my_dest_ptr)cinfo->dest;
 709         dest->buffer = (unsigned char*)cinfo->mem->alloc_small ((j_common_ptr) cinfo, JPOOL_IMAGE, JPEG_OUTPUT_BUF_SIZE * sizeof(unsigned char));
 710         dest->pub.next_output_byte = dest->buffer;
 711         dest->pub.free_in_buffer = JPEG_OUTPUT_BUF_SIZE;
 712 }
 713
 714 static jboolean JPEG_EmptyOutputBuffer (j_compress_ptr cinfo)
 715 {
 716         my_dest_ptr dest = (my_dest_ptr)cinfo->dest;
 717
 718         if (FS_Write (dest->outfile, dest->buffer, JPEG_OUTPUT_BUF_SIZE) != (size_t) JPEG_OUTPUT_BUF_SIZE)
 719                 longjmp(error_in_jpeg, 1);
 720
 721         dest->pub.next_output_byte = dest->buffer;
 722         dest->pub.free_in_buffer = JPEG_OUTPUT_BUF_SIZE;
 723         return true;
 724 }
 725
 726 static void JPEG_TermDestination (j_compress_ptr cinfo)
 727 {
 728         my_dest_ptr dest = (my_dest_ptr)cinfo->dest;
 729         size_t datacount = JPEG_OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
 730
 731         // Write any data remaining in the buffer
 732         if (datacount > 0)
 733                 if (FS_Write (dest->outfile, dest->buffer, datacount) != (fs_offset_t)datacount)
 734                         longjmp(error_in_jpeg, 1);
 735 }
 736
 737 static void JPEG_FileDest (j_compress_ptr cinfo, qfile_t* outfile)
 738 {
 739         my_dest_ptr dest;
 740
 741         // First time for this JPEG object?
 742         if (cinfo->dest == NULL)
 743                 cinfo->dest = (struct jpeg_destination_mgr *)(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, sizeof(my_destination_mgr));
 744
 745         dest = (my_dest_ptr)cinfo->dest;
 746         dest->pub.init_destination = JPEG_InitDestination;
 747         dest->pub.empty_output_buffer = JPEG_EmptyOutputBuffer;
 748         dest->pub.term_destination = JPEG_TermDestination;
 749         dest->outfile = outfile;
 750 }
 751
 752 static void JPEG_Mem_InitDestination (j_compress_ptr cinfo)
 753 {
 754         my_dest_ptr dest = (my_dest_ptr)cinfo->dest;
 755         dest->pub.next_output_byte = dest->buffer;
 756         dest->pub.free_in_buffer = dest->bufsize;
 757 }
 758
 759 static jboolean JPEG_Mem_EmptyOutputBuffer (j_compress_ptr cinfo)
 760 {
 761         my_dest_ptr dest = (my_dest_ptr)cinfo->dest;
 762         jpeg_toolarge = true;
 763         dest->pub.next_output_byte = dest->buffer;
 764         dest->pub.free_in_buffer = dest->bufsize;
 765         return true;
 766 }
 767
 768 static void JPEG_Mem_TermDestination (j_compress_ptr cinfo)
 769 {
 770         my_dest_ptr dest = (my_dest_ptr)cinfo->dest;
 771         dest->bufsize = dest->pub.next_output_byte - dest->buffer;
 772 }
 773 static void JPEG_MemDest (j_compress_ptr cinfo, void* buf, size_t bufsize)
 774 {
 775         my_dest_ptr dest;
 776
 777         // First time for this JPEG object?
 778         if (cinfo->dest == NULL)
 779                 cinfo->dest = (struct jpeg_destination_mgr *)(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, sizeof(my_destination_mgr));
 780
 781         dest = (my_dest_ptr)cinfo->dest;
 782         dest->pub.init_destination = JPEG_Mem_InitDestination;
 783         dest->pub.empty_output_buffer = JPEG_Mem_EmptyOutputBuffer;
 784         dest->pub.term_destination = JPEG_Mem_TermDestination;
 785         dest->outfile = NULL;
 786
 787         dest->buffer = (unsigned char *) buf;
 788         dest->bufsize = bufsize;
 789 }
 790
 791
 792 /*
 793 ====================
 794 JPEG_SaveImage_preflipped
 795
 796 Save a preflipped JPEG image to a file
 797 ====================
 798 */
 799 qboolean JPEG_SaveImage_preflipped (const char *filename, int width, int height, unsigned char *data)
 800 {
 801         struct jpeg_compress_struct cinfo;
 802         struct jpeg_error_mgr jerr;
 803         unsigned char *scanline;
 804         unsigned int offset, linesize;
 805         qfile_t* file;
 806
 807         // No DLL = no JPEGs
 808         if (!jpeg_dll)
 809         {
 810                 Con_Print("You need the libjpeg library to save JPEG images\n");
 811                 return false;
 812         }
 813
 814         // Open the file
 815         file = FS_OpenRealFile(filename, "wb", true);
 816         if (!file)
 817                 return false;
 818
 819         if(setjmp(error_in_jpeg))
 820                 goto error_caught;
 821         cinfo.err = qjpeg_std_error (&jerr);
 822         cinfo.err->error_exit = JPEG_ErrorExit;
 823
 824         qjpeg_create_compress (&cinfo);
 825         JPEG_FileDest (&cinfo, file);
 826
 827         // Set the parameters for compression
 828         cinfo.image_width = width;
 829         cinfo.image_height = height;
 830         cinfo.in_color_space = JCS_RGB;
 831         cinfo.input_components = 3;
 832         qjpeg_set_defaults (&cinfo);
 833         qjpeg_set_quality (&cinfo, (int)(scr_screenshot_jpeg_quality.value * 100), TRUE);
 834
 835         // turn off subsampling (to make text look better)
 836         cinfo.optimize_coding = 1;
 837         cinfo.comp_info[0].h_samp_factor = 1;
 838         cinfo.comp_info[0].v_samp_factor = 1;
 839         cinfo.comp_info[1].h_samp_factor = 1;
 840         cinfo.comp_info[1].v_samp_factor = 1;
 841         cinfo.comp_info[2].h_samp_factor = 1;
 842         cinfo.comp_info[2].v_samp_factor = 1;
 843
 844         qjpeg_start_compress (&cinfo, true);
 845
 846         // Compress each scanline
 847         linesize = cinfo.image_width * 3;
 848         offset = linesize * (cinfo.image_height - 1);
 849         while (cinfo.next_scanline < cinfo.image_height)
 850         {
 851                 scanline = &data[offset - cinfo.next_scanline * linesize];
 852
 853                 qjpeg_write_scanlines (&cinfo, &scanline, 1);
 854         }
 855
 856         qjpeg_finish_compress (&cinfo);
 857         qjpeg_destroy_compress (&cinfo);
 858
 859         FS_Close (file);
 860         return true;
 861
 862 error_caught:
 863         qjpeg_destroy_compress (&cinfo);
 864         FS_Close (file);
 865         return false;
 866 }
 867
 868 static size_t JPEG_try_SaveImage_to_Buffer (struct jpeg_compress_struct *cinfo, char *jpegbuf, size_t jpegsize, int quality, int width, int height, unsigned char *data)
 869 {
 870         unsigned char *scanline;
 871         unsigned int linesize;
 872
 873         jpeg_toolarge = false;
 874         JPEG_MemDest (cinfo, jpegbuf, jpegsize);
 875
 876         // Set the parameters for compression
 877         cinfo->image_width = width;
 878         cinfo->image_height = height;
 879         cinfo->in_color_space = JCS_RGB;
 880         cinfo->input_components = 3;
 881         qjpeg_set_defaults (cinfo);
 882         qjpeg_set_quality (cinfo, quality, FALSE);
 883
 884         cinfo->comp_info[0].h_samp_factor = 2;
 885         cinfo->comp_info[0].v_samp_factor = 2;
 886         cinfo->comp_info[1].h_samp_factor = 1;
 887         cinfo->comp_info[1].v_samp_factor = 1;
 888         cinfo->comp_info[2].h_samp_factor = 1;
 889         cinfo->comp_info[2].v_samp_factor = 1;
 890         cinfo->optimize_coding = 1;
 891
 892         qjpeg_start_compress (cinfo, true);
 893
 894         // Compress each scanline
 895         linesize = width * 3;
 896         while (cinfo->next_scanline < cinfo->image_height)
 897         {
 898                 scanline = &data[cinfo->next_scanline * linesize];
 899
 900                 qjpeg_write_scanlines (cinfo, &scanline, 1);
 901         }
 902
 903         qjpeg_finish_compress (cinfo);
 904
 905         if(jpeg_toolarge)
 906                 return 0;
 907
 908         return ((my_dest_ptr) cinfo->dest)->bufsize;
 909 }
 910
 911 size_t JPEG_SaveImage_to_Buffer (char *jpegbuf, size_t jpegsize, int width, int height, unsigned char *data)
 912 {
 913         struct jpeg_compress_struct cinfo;
 914         struct jpeg_error_mgr jerr;
 915
 916         int quality;
 917         int quality_guess;
 918         size_t result;
 919
 920         // No DLL = no JPEGs
 921         if (!jpeg_dll)
 922         {
 923                 Con_Print("You need the libjpeg library to save JPEG images\n");
 924                 return false;
 925         }
 926
 927         if(setjmp(error_in_jpeg))
 928                 goto error_caught;
 929         cinfo.err = qjpeg_std_error (&jerr);
 930         cinfo.err->error_exit = JPEG_ErrorExit;
 931
 932         qjpeg_create_compress (&cinfo);
 933
 934 #if 0
 935         // used to get the formula below
 936         {
 937                 char buf[1048576];
 938                 unsigned char *img;
 939                 int i;
 940
 941                 img = Mem_Alloc(tempmempool, width * height * 3);
 942                 for(i = 0; i < width * height * 3; ++i)
 943                         img[i] = rand() & 0xFF;
 944
 945                 for(i = 0; i <= 100; ++i)
 946                 {
 947                         Con_Printf("! %d %d %d %d\n", width, height, i, (int) JPEG_try_SaveImage_to_Buffer(&cinfo, buf, sizeof(buf), i, width, height, img));
 948                 }
 949
 950                 Mem_Free(img);
 951         }
 952 #endif
 953
 954         //quality_guess = (100 * jpegsize - 41000) / (width*height) + 2; // fits random data
 955         quality_guess   = (256 * jpegsize - 81920) / (width*height) - 8; // fits Nexuiz's map pictures
 956
 957         quality_guess = bound(0, quality_guess, 100);
 958         quality = bound(0, quality_guess + sv_writepicture_quality.integer, 100); // assume it can do 10 failed attempts
 959
 960         while(!(result = JPEG_try_SaveImage_to_Buffer(&cinfo, jpegbuf, jpegsize, quality, width, height, data)))
 961         {
 962                 --quality;
 963                 if(quality < 0)
 964                 {
 965                         Con_Printf("couldn't write image at all, probably too big\n");
 966                         return 0;
 967                 }
 968         }
 969         qjpeg_destroy_compress (&cinfo);
 970         Con_DPrintf("JPEG_SaveImage_to_Buffer: guessed quality/size %d/%d, actually got %d/%d\n", quality_guess, (int)jpegsize, quality, (int)result);
 971
 972         return result;
 973
 974 error_caught:
 975         qjpeg_destroy_compress (&cinfo);
 976         return 0;
 977 }
 978
 979 typedef struct CompressedImageCacheItem
 980 {
 981         char imagename[MAX_QPATH];
 982         size_t maxsize;
 983         void *compressed;
 984         size_t compressed_size;
 985         struct CompressedImageCacheItem *next;
 986 }
 987 CompressedImageCacheItem;
 988 #define COMPRESSEDIMAGECACHE_SIZE 4096
 989 static CompressedImageCacheItem *CompressedImageCache[COMPRESSEDIMAGECACHE_SIZE];
 990
 991 static void CompressedImageCache_Add(const char *imagename, size_t maxsize, void *compressed, size_t compressed_size)
 992 {
 993         const char *hashkey = va("%s:%d", imagename, (int) maxsize);
 994         int hashindex = CRC_Block((unsigned char *) hashkey, strlen(hashkey)) % COMPRESSEDIMAGECACHE_SIZE;
 995         CompressedImageCacheItem *i;
 996
 997         if(strlen(imagename) >= MAX_QPATH)
 998                 return; // can't add this
 999
1000         i = (CompressedImageCacheItem*) Z_Malloc(sizeof(CompressedImageCacheItem));
1001         strlcpy(i->imagename, imagename, sizeof(i->imagename));
1002         i->maxsize = maxsize;
1003         i->compressed = compressed;
1004         i->compressed_size = compressed_size;
1005         i->next = CompressedImageCache[hashindex];
1006         CompressedImageCache[hashindex] = i;
1007 }
1008
1009 static CompressedImageCacheItem *CompressedImageCache_Find(const char *imagename, size_t maxsize)
1010 {
1011         const char *hashkey = va("%s:%d", imagename, (int) maxsize);
1012         int hashindex = CRC_Block((unsigned char *) hashkey, strlen(hashkey)) % COMPRESSEDIMAGECACHE_SIZE;
1013         CompressedImageCacheItem *i = CompressedImageCache[hashindex];
1014
1015         while(i)
1016         {
1017                 if(i->maxsize == maxsize)
1018                         if(!strcmp(i->imagename, imagename))
1019                                 return i;
1020                 i = i->next;
1021         }
1022         return NULL;
1023 }
1024
1025 qboolean Image_Compress(const char *imagename, size_t maxsize, void **buf, size_t *size)
1026 {
1027         unsigned char *imagedata, *newimagedata;
1028         int maxPixelCount;
1029         int components[3] = {2, 1, 0};
1030         CompressedImageCacheItem *i;
1031
1032         JPEG_OpenLibrary (); // for now; LH had the idea of replacing this by a better format
1033
1034         // No DLL = no JPEGs
1035         if (!jpeg_dll)
1036         {
1037                 Con_Print("You need the libjpeg library to save JPEG images\n");
1038                 return false;
1039         }
1040
1041         i = CompressedImageCache_Find(imagename, maxsize);
1042         if(i)
1043         {
1044                 *size = i->compressed_size;
1045                 *buf = i->compressed;
1046         }
1047
1048         // load the image
1049         imagedata = loadimagepixelsbgra(imagename, true, false);
1050         if(!imagedata)
1051                 return false;
1052
1053         // find an appropriate size for somewhat okay compression
1054         if(maxsize <= 768)
1055                 maxPixelCount = 32 * 32;
1056         else if(maxsize <= 1024)
1057                 maxPixelCount = 64 * 64;
1058         else if(maxsize <= 4096)
1059                 maxPixelCount = 128 * 128;
1060         else
1061                 maxPixelCount = 256 * 256;
1062
1063         while(image_width * image_height > maxPixelCount)
1064         {
1065                 int one = 1;
1066                 Image_MipReduce32(imagedata, imagedata, &image_width, &image_height, &one, image_width/2, image_height/2, 1);
1067         }
1068
1069         newimagedata = (unsigned char *) Mem_Alloc(tempmempool, image_width * image_height * 3);
1070
1071         // convert the image from BGRA to RGB
1072         Image_CopyMux(newimagedata, imagedata, image_width, image_height, false, false, false, 3, 4, components);
1073         Mem_Free(imagedata);
1074
1075         // try to compress it to JPEG
1076         *buf = Z_Malloc(maxsize);
1077         *size = JPEG_SaveImage_to_Buffer((char *) *buf, maxsize, image_width, image_height, newimagedata);
1078         Mem_Free(newimagedata);
1079
1080         if(!*size)
1081         {
1082                 Z_Free(*buf);
1083                 *buf = NULL;
1084                 Con_Printf("could not compress image %s to %d bytes\n", imagename, (int)maxsize);
1085                 // return false;
1086                 // also cache failures!
1087         }
1088
1089         // store it in the cache
1090         CompressedImageCache_Add(imagename, maxsize, *buf, *size);
1091         return (*buf != NULL);
1092 }