jcmaster.c File Reference

#include "jinclude.h"
#include "jpeglib.h"

Go to the source code of this file.

Data Structures

struct  my_comp_master

Defines

#define JPEG_INTERNALS

Typedefs

typedef my_comp_mastermy_master_ptr

Enumerations

enum  c_pass_type { main_pass, huff_opt_pass, output_pass }

Functions

 finish_pass_master (j_compress_ptr cinfo)
 initial_setup (j_compress_ptr cinfo)
 jinit_c_master_control (j_compress_ptr cinfo, boolean transcode_only)
 pass_startup (j_compress_ptr cinfo)
 per_scan_setup (j_compress_ptr cinfo)
 prepare_for_pass (j_compress_ptr cinfo)
 select_scan_parameters (j_compress_ptr cinfo)


Define Documentation

#define JPEG_INTERNALS

Definition at line 14 of file jcmaster.c.


Typedef Documentation

Definition at line 38 of file jcmaster.c.


Enumeration Type Documentation

Enumerator:
main_pass 
huff_opt_pass 
output_pass 

Definition at line 21 of file jcmaster.c.

00021              {
00022     main_pass,      /* input data, also do first output step */
00023     huff_opt_pass,      /* Huffman code optimization pass */
00024     output_pass     /* data output pass */
00025 } c_pass_type;


Function Documentation

finish_pass_master ( j_compress_ptr  cinfo  ) 

Definition at line 503 of file jcmaster.c.

References huff_opt_pass, main_pass, output_pass, my_comp_master::pass_number, my_comp_master::pass_type, and my_comp_master::scan_number.

Referenced by jinit_c_master_control().

00504 {
00505   my_master_ptr master = (my_master_ptr) cinfo->master;
00506 
00507   /* The entropy coder always needs an end-of-pass call,
00508    * either to analyze statistics or to flush its output buffer.
00509    */
00510   (*cinfo->entropy->finish_pass) (cinfo);
00511 
00512   /* Update state for next pass */
00513   switch (master->pass_type) {
00514   case main_pass:
00515     /* next pass is either output of scan 0 (after optimization)
00516      * or output of scan 1 (if no optimization).
00517      */
00518     master->pass_type = output_pass;
00519     if (! cinfo->optimize_coding)
00520       master->scan_number++;
00521     break;
00522   case huff_opt_pass:
00523     /* next pass is always output of current scan */
00524     master->pass_type = output_pass;
00525     break;
00526   case output_pass:
00527     /* next pass is either optimization or output of next scan */
00528     if (cinfo->optimize_coding)
00529       master->pass_type = huff_opt_pass;
00530     master->scan_number++;
00531     break;
00532   }
00533 
00534   master->pass_number++;
00535 }

initial_setup ( j_compress_ptr  cinfo  ) 

Definition at line 46 of file jcmaster.c.

References BITS_IN_JSAMPLE, jpeg_component_info::component_index, jpeg_component_info::component_needed, compptr, jpeg_component_info::DCT_scaled_size, DCTSIZE, jpeg_component_info::downsampled_height, jpeg_component_info::downsampled_width, ERREXIT, ERREXIT1, ERREXIT2, jpeg_component_info::h_samp_factor, jpeg_component_info::height_in_blocks, jdiv_round_up(), JPEG_MAX_DIMENSION, MAX, MAX_COMPONENTS, MAX_SAMP_FACTOR, TRUE, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks.

Referenced by consume_markers(), and jinit_c_master_control().

00048 {
00049   int ci;
00050   jpeg_component_info *compptr;
00051   long samplesperrow;
00052   JDIMENSION jd_samplesperrow;
00053 
00054   /* Sanity check on image dimensions */
00055   if (cinfo->image_height <= 0 || cinfo->image_width <= 0
00056       || cinfo->num_components <= 0 || cinfo->input_components <= 0)
00057     ERREXIT(cinfo, JERR_EMPTY_IMAGE);
00058 
00059   /* Make sure image isn't bigger than I can handle */
00060   if ((long) cinfo->image_height > (long) JPEG_MAX_DIMENSION ||
00061       (long) cinfo->image_width > (long) JPEG_MAX_DIMENSION)
00062     ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) JPEG_MAX_DIMENSION);
00063 
00064   /* Width of an input scanline must be representable as JDIMENSION. */
00065   samplesperrow = (long) cinfo->image_width * (long) cinfo->input_components;
00066   jd_samplesperrow = (JDIMENSION) samplesperrow;
00067   if ((long) jd_samplesperrow != samplesperrow)
00068     ERREXIT(cinfo, JERR_WIDTH_OVERFLOW);
00069 
00070   /* For now, precision must match compiled-in value... */
00071   if (cinfo->data_precision != BITS_IN_JSAMPLE)
00072     ERREXIT1(cinfo, JERR_BAD_PRECISION, cinfo->data_precision);
00073 
00074   /* Check that number of components won't exceed internal array sizes */
00075   if (cinfo->num_components > MAX_COMPONENTS)
00076     ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
00077          MAX_COMPONENTS);
00078 
00079   /* Compute maximum sampling factors; check factor validity */
00080   cinfo->max_h_samp_factor = 1;
00081   cinfo->max_v_samp_factor = 1;
00082   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
00083        ci++, compptr++) {
00084     if (compptr->h_samp_factor<=0 || compptr->h_samp_factor>MAX_SAMP_FACTOR ||
00085     compptr->v_samp_factor<=0 || compptr->v_samp_factor>MAX_SAMP_FACTOR)
00086       ERREXIT(cinfo, JERR_BAD_SAMPLING);
00087     cinfo->max_h_samp_factor = MAX(cinfo->max_h_samp_factor,
00088                    compptr->h_samp_factor);
00089     cinfo->max_v_samp_factor = MAX(cinfo->max_v_samp_factor,
00090                    compptr->v_samp_factor);
00091   }
00092 
00093   /* Compute dimensions of components */
00094   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
00095        ci++, compptr++) {
00096     /* Fill in the correct component_index value; don't rely on application */
00097     compptr->component_index = ci;
00098     /* For compression, we never do DCT scaling. */
00099     compptr->DCT_scaled_size = DCTSIZE;
00100     /* Size in DCT blocks */
00101     compptr->width_in_blocks = (JDIMENSION)
00102       jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
00103             (long) (cinfo->max_h_samp_factor * DCTSIZE));
00104     compptr->height_in_blocks = (JDIMENSION)
00105       jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
00106             (long) (cinfo->max_v_samp_factor * DCTSIZE));
00107     /* Size in samples */
00108     compptr->downsampled_width = (JDIMENSION)
00109       jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
00110             (long) cinfo->max_h_samp_factor);
00111     compptr->downsampled_height = (JDIMENSION)
00112       jdiv_round_up((long) cinfo->image_height * (long) compptr->v_samp_factor,
00113             (long) cinfo->max_v_samp_factor);
00114     /* Mark component needed (this flag isn't actually used for compression) */
00115     compptr->component_needed = TRUE;
00116   }
00117 
00118   /* Compute number of fully interleaved MCU rows (number of times that
00119    * main controller will call coefficient controller).
00120    */
00121   cinfo->total_iMCU_rows = (JDIMENSION)
00122     jdiv_round_up((long) cinfo->image_height,
00123           (long) (cinfo->max_v_samp_factor*DCTSIZE));
00124 }

jinit_c_master_control ( j_compress_ptr  cinfo,
boolean  transcode_only 
)

Definition at line 543 of file jcmaster.c.

References ERREXIT, FALSE, finish_pass_master(), huff_opt_pass, initial_setup(), jpeg_comp_master::is_last_pass, JPOOL_IMAGE, main_pass, output_pass, my_comp_master::pass_number, pass_startup(), my_comp_master::pass_type, prepare_for_pass(), my_comp_master::pub, my_comp_master::scan_number, SIZEOF, my_comp_master::total_passes, and TRUE.

Referenced by jinit_compress_master(), and transencode_master_selection().

00544 {
00545   my_master_ptr master;
00546 
00547   master = (my_master_ptr)
00548       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
00549                   SIZEOF(my_comp_master));
00550   cinfo->master = (struct jpeg_comp_master *) master;
00551   master->pub.prepare_for_pass = prepare_for_pass;
00552   master->pub.pass_startup = pass_startup;
00553   master->pub.finish_pass = finish_pass_master;
00554   master->pub.is_last_pass = FALSE;
00555 
00556   /* Validate parameters, determine derived values */
00557   initial_setup(cinfo);
00558 
00559   if (cinfo->scan_info != NULL) {
00560 #ifdef C_MULTISCAN_FILES_SUPPORTED
00561     validate_script(cinfo);
00562 #else
00563     ERREXIT(cinfo, JERR_NOT_COMPILED);
00564 #endif
00565   } else {
00566     cinfo->progressive_mode = FALSE;
00567     cinfo->num_scans = 1;
00568   }
00569 
00570   if (cinfo->progressive_mode)  /*  TEMPORARY HACK ??? */
00571     cinfo->optimize_coding = TRUE; /* assume default tables no good for progressive mode */
00572 
00573   /* Initialize my private state */
00574   if (transcode_only) {
00575     /* no main pass in transcoding */
00576     if (cinfo->optimize_coding)
00577       master->pass_type = huff_opt_pass;
00578     else
00579       master->pass_type = output_pass;
00580   } else {
00581     /* for normal compression, first pass is always this type: */
00582     master->pass_type = main_pass;
00583   }
00584   master->scan_number = 0;
00585   master->pass_number = 0;
00586   if (cinfo->optimize_coding)
00587     master->total_passes = cinfo->num_scans * 2;
00588   else
00589     master->total_passes = cinfo->num_scans;
00590 }

pass_startup ( j_compress_ptr  cinfo  ) 

Definition at line 489 of file jcmaster.c.

References FALSE.

Referenced by jinit_c_master_control().

00490 {
00491   cinfo->master->call_pass_startup = FALSE; /* reset flag so call only once */
00492 
00493   (*cinfo->marker->write_frame_header) (cinfo);
00494   (*cinfo->marker->write_scan_header) (cinfo);
00495 }

per_scan_setup ( j_compress_ptr  cinfo  ) 

Definition at line 308 of file jcmaster.c.

References C_MAX_BLOCKS_IN_MCU, compptr, DCTSIZE, ERREXIT, ERREXIT2, jpeg_component_info::h_samp_factor, jpeg_component_info::height_in_blocks, jdiv_round_up(), jpeg_component_info::last_col_width, jpeg_component_info::last_row_height, jpeg_component_info::MCU_blocks, jpeg_component_info::MCU_height, jpeg_component_info::MCU_sample_width, jpeg_component_info::MCU_width, MIN, jpeg_component_info::v_samp_factor, and jpeg_component_info::width_in_blocks.

Referenced by prepare_for_pass(), and start_input_pass().

00311 {
00312   int ci, mcublks, tmp;
00313   jpeg_component_info *compptr;
00314   
00315   if (cinfo->comps_in_scan == 1) {
00316     
00317     /* Noninterleaved (single-component) scan */
00318     compptr = cinfo->cur_comp_info[0];
00319     
00320     /* Overall image size in MCUs */
00321     cinfo->MCUs_per_row = compptr->width_in_blocks;
00322     cinfo->MCU_rows_in_scan = compptr->height_in_blocks;
00323     
00324     /* For noninterleaved scan, always one block per MCU */
00325     compptr->MCU_width = 1;
00326     compptr->MCU_height = 1;
00327     compptr->MCU_blocks = 1;
00328     compptr->MCU_sample_width = DCTSIZE;
00329     compptr->last_col_width = 1;
00330     /* For noninterleaved scans, it is convenient to define last_row_height
00331      * as the number of block rows present in the last iMCU row.
00332      */
00333     tmp = (int) (compptr->height_in_blocks % compptr->v_samp_factor);
00334     if (tmp == 0) tmp = compptr->v_samp_factor;
00335     compptr->last_row_height = tmp;
00336     
00337     /* Prepare array describing MCU composition */
00338     cinfo->blocks_in_MCU = 1;
00339     cinfo->MCU_membership[0] = 0;
00340     
00341   } else {
00342     
00343     /* Interleaved (multi-component) scan */
00344     if (cinfo->comps_in_scan <= 0 || cinfo->comps_in_scan > MAX_COMPS_IN_SCAN)
00345       ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->comps_in_scan,
00346            MAX_COMPS_IN_SCAN);
00347     
00348     /* Overall image size in MCUs */
00349     cinfo->MCUs_per_row = (JDIMENSION)
00350       jdiv_round_up((long) cinfo->image_width,
00351             (long) (cinfo->max_h_samp_factor*DCTSIZE));
00352     cinfo->MCU_rows_in_scan = (JDIMENSION)
00353       jdiv_round_up((long) cinfo->image_height,
00354             (long) (cinfo->max_v_samp_factor*DCTSIZE));
00355     
00356     cinfo->blocks_in_MCU = 0;
00357     
00358     for (ci = 0; ci < cinfo->comps_in_scan; ci++) {
00359       compptr = cinfo->cur_comp_info[ci];
00360       /* Sampling factors give # of blocks of component in each MCU */
00361       compptr->MCU_width = compptr->h_samp_factor;
00362       compptr->MCU_height = compptr->v_samp_factor;
00363       compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
00364       compptr->MCU_sample_width = compptr->MCU_width * DCTSIZE;
00365       /* Figure number of non-dummy blocks in last MCU column & row */
00366       tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
00367       if (tmp == 0) tmp = compptr->MCU_width;
00368       compptr->last_col_width = tmp;
00369       tmp = (int) (compptr->height_in_blocks % compptr->MCU_height);
00370       if (tmp == 0) tmp = compptr->MCU_height;
00371       compptr->last_row_height = tmp;
00372       /* Prepare array describing MCU composition */
00373       mcublks = compptr->MCU_blocks;
00374       if (cinfo->blocks_in_MCU + mcublks > C_MAX_BLOCKS_IN_MCU)
00375     ERREXIT(cinfo, JERR_BAD_MCU_SIZE);
00376       while (mcublks-- > 0) {
00377     cinfo->MCU_membership[cinfo->blocks_in_MCU++] = ci;
00378       }
00379     }
00380     
00381   }
00382 
00383   /* Convert restart specified in rows to actual MCU count. */
00384   /* Note that count must fit in 16 bits, so we provide limiting. */
00385   if (cinfo->restart_in_rows > 0) {
00386     long nominal = (long) cinfo->restart_in_rows * (long) cinfo->MCUs_per_row;
00387     cinfo->restart_interval = (unsigned int) MIN(nominal, 65535L);
00388   }
00389 }

prepare_for_pass ( j_compress_ptr  cinfo  ) 

Definition at line 401 of file jcmaster.c.

References jpeg_comp_master::call_pass_startup, ERREXIT, FALSE, huff_opt_pass, jpeg_comp_master::is_last_pass, JBUF_CRANK_DEST, JBUF_PASS_THRU, JBUF_SAVE_AND_PASS, main_pass, output_pass, my_comp_master::pass_number, my_comp_master::pass_type, per_scan_setup(), my_comp_master::pub, my_comp_master::scan_number, select_scan_parameters(), my_comp_master::total_passes, and TRUE.

Referenced by jinit_c_master_control().

00402 {
00403   my_master_ptr master = (my_master_ptr) cinfo->master;
00404 
00405   switch (master->pass_type) {
00406   case main_pass:
00407     /* Initial pass: will collect input data, and do either Huffman
00408      * optimization or data output for the first scan.
00409      */
00410     select_scan_parameters(cinfo);
00411     per_scan_setup(cinfo);
00412     if (! cinfo->raw_data_in) {
00413       (*cinfo->cconvert->start_pass) (cinfo);
00414       (*cinfo->downsample->start_pass) (cinfo);
00415       (*cinfo->prep->start_pass) (cinfo, JBUF_PASS_THRU);
00416     }
00417     (*cinfo->fdct->start_pass) (cinfo);
00418     (*cinfo->entropy->start_pass) (cinfo, cinfo->optimize_coding);
00419     (*cinfo->coef->start_pass) (cinfo,
00420                 (master->total_passes > 1 ?
00421                  JBUF_SAVE_AND_PASS : JBUF_PASS_THRU));
00422     (*cinfo->main->start_pass) (cinfo, JBUF_PASS_THRU);
00423     if (cinfo->optimize_coding) {
00424       /* No immediate data output; postpone writing frame/scan headers */
00425       master->pub.call_pass_startup = FALSE;
00426     } else {
00427       /* Will write frame/scan headers at first jpeg_write_scanlines call */
00428       master->pub.call_pass_startup = TRUE;
00429     }
00430     break;
00431 #ifdef ENTROPY_OPT_SUPPORTED
00432   case huff_opt_pass:
00433     /* Do Huffman optimization for a scan after the first one. */
00434     select_scan_parameters(cinfo);
00435     per_scan_setup(cinfo);
00436     if (cinfo->Ss != 0 || cinfo->Ah == 0 || cinfo->arith_code) {
00437       (*cinfo->entropy->start_pass) (cinfo, TRUE);
00438       (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
00439       master->pub.call_pass_startup = FALSE;
00440       break;
00441     }
00442     /* Special case: Huffman DC refinement scans need no Huffman table
00443      * and therefore we can skip the optimization pass for them.
00444      */
00445     master->pass_type = output_pass;
00446     master->pass_number++;
00447     /*FALLTHROUGH*/
00448 #endif
00449   case output_pass:
00450     /* Do a data-output pass. */
00451     /* We need not repeat per-scan setup if prior optimization pass did it. */
00452     if (! cinfo->optimize_coding) {
00453       select_scan_parameters(cinfo);
00454       per_scan_setup(cinfo);
00455     }
00456     (*cinfo->entropy->start_pass) (cinfo, FALSE);
00457     (*cinfo->coef->start_pass) (cinfo, JBUF_CRANK_DEST);
00458     /* We emit frame/scan headers now */
00459     if (master->scan_number == 0)
00460       (*cinfo->marker->write_frame_header) (cinfo);
00461     (*cinfo->marker->write_scan_header) (cinfo);
00462     master->pub.call_pass_startup = FALSE;
00463     break;
00464   default:
00465     ERREXIT(cinfo, JERR_NOT_COMPILED);
00466   }
00467 
00468   master->pub.is_last_pass = (master->pass_number == master->total_passes-1);
00469 
00470   /* Set up progress monitor's pass info if present */
00471   if (cinfo->progress != NULL) {
00472     cinfo->progress->completed_passes = master->pass_number;
00473     cinfo->progress->total_passes = master->total_passes;
00474   }
00475 }

select_scan_parameters ( j_compress_ptr  cinfo  ) 

Definition at line 267 of file jcmaster.c.

References jpeg_scan_info::Ah, jpeg_scan_info::Al, jpeg_scan_info::component_index, jpeg_scan_info::comps_in_scan, DCTSIZE2, ERREXIT2, my_comp_master::scan_number, jpeg_scan_info::Se, and jpeg_scan_info::Ss.

Referenced by prepare_for_pass().

00269 {
00270   int ci;
00271 
00272 #ifdef C_MULTISCAN_FILES_SUPPORTED
00273   if (cinfo->scan_info != NULL) {
00274     /* Prepare for current scan --- the script is already validated */
00275     my_master_ptr master = (my_master_ptr) cinfo->master;
00276     const jpeg_scan_info * scanptr = cinfo->scan_info + master->scan_number;
00277 
00278     cinfo->comps_in_scan = scanptr->comps_in_scan;
00279     for (ci = 0; ci < scanptr->comps_in_scan; ci++) {
00280       cinfo->cur_comp_info[ci] =
00281     &cinfo->comp_info[scanptr->component_index[ci]];
00282     }
00283     cinfo->Ss = scanptr->Ss;
00284     cinfo->Se = scanptr->Se;
00285     cinfo->Ah = scanptr->Ah;
00286     cinfo->Al = scanptr->Al;
00287   }
00288   else
00289 #endif
00290   {
00291     /* Prepare for single sequential-JPEG scan containing all components */
00292     if (cinfo->num_components > MAX_COMPS_IN_SCAN)
00293       ERREXIT2(cinfo, JERR_COMPONENT_COUNT, cinfo->num_components,
00294            MAX_COMPS_IN_SCAN);
00295     cinfo->comps_in_scan = cinfo->num_components;
00296     for (ci = 0; ci < cinfo->num_components; ci++) {
00297       cinfo->cur_comp_info[ci] = &cinfo->comp_info[ci];
00298     }
00299     cinfo->Ss = 0;
00300     cinfo->Se = DCTSIZE2-1;
00301     cinfo->Ah = 0;
00302     cinfo->Al = 0;
00303   }
00304 }


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