diff options
Diffstat (limited to '3rdparty/libjpeg/jdmainct.c')
-rw-r--r-- | 3rdparty/libjpeg/jdmainct.c | 92 |
1 files changed, 45 insertions, 47 deletions
diff --git a/3rdparty/libjpeg/jdmainct.c b/3rdparty/libjpeg/jdmainct.c index 52091fb2bed..1cd66d853bf 100644 --- a/3rdparty/libjpeg/jdmainct.c +++ b/3rdparty/libjpeg/jdmainct.c @@ -2,7 +2,7 @@ * jdmainct.c * * Copyright (C) 1994-1996, Thomas G. Lane. - * Modified 2002-2012 by Guido Vollbeding. + * Modified 2002-2020 by Guido Vollbeding. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * @@ -26,8 +26,8 @@ * trivial. Its responsibility is to provide context rows for upsampling/ * rescaling, and doing this in an efficient fashion is a bit tricky. * - * Postprocessor input data is counted in "row groups". A row group - * is defined to be (v_samp_factor * DCT_scaled_size / min_DCT_scaled_size) + * Postprocessor input data is counted in "row groups". A row group is + * defined to be (v_samp_factor * DCT_v_scaled_size / min_DCT_v_scaled_size) * sample rows of each component. (We require DCT_scaled_size values to be * chosen such that these numbers are integers. In practice DCT_scaled_size * values will likely be powers of two, so we actually have the stronger @@ -37,8 +37,8 @@ * applying). * * The coefficient controller will deliver data to us one iMCU row at a time; - * each iMCU row contains v_samp_factor * DCT_scaled_size sample rows, or - * exactly min_DCT_scaled_size row groups. (This amount of data corresponds + * each iMCU row contains v_samp_factor * DCT_v_scaled_size sample rows, or + * exactly min_DCT_v_scaled_size row groups. (This amount of data corresponds * to one row of MCUs when the image is fully interleaved.) Note that the * number of sample rows varies across components, but the number of row * groups does not. Some garbage sample rows may be included in the last iMCU @@ -75,7 +75,7 @@ * We could do this most simply by copying data around in our buffer, but * that'd be very slow. We can avoid copying any data by creating a rather * strange pointer structure. Here's how it works. We allocate a workspace - * consisting of M+2 row groups (where M = min_DCT_scaled_size is the number + * consisting of M+2 row groups (where M = min_DCT_v_scaled_size is the number * of row groups per iMCU row). We create two sets of redundant pointers to * the workspace. Labeling the physical row groups 0 to M+1, the synthesized * pointer lists look like this: @@ -100,11 +100,11 @@ * the first or last sample row as necessary (this is cheaper than copying * sample rows around). * - * This scheme breaks down if M < 2, ie, min_DCT_scaled_size is 1. In that + * This scheme breaks down if M < 2, ie, min_DCT_v_scaled_size is 1. In that * situation each iMCU row provides only one row group so the buffering logic * must be different (eg, we must read two iMCU rows before we can emit the * first row group). For now, we simply do not support providing context - * rows when min_DCT_scaled_size is 1. That combination seems unlikely to + * rows when min_DCT_v_scaled_size is 1. That combination seems unlikely to * be worth providing --- if someone wants a 1/8th-size preview, they probably * want it quick and dirty, so a context-free upsampler is sufficient. */ @@ -118,17 +118,18 @@ typedef struct { /* Pointer to allocated workspace (M or M+2 row groups). */ JSAMPARRAY buffer[MAX_COMPONENTS]; - boolean buffer_full; /* Have we gotten an iMCU row from decoder? */ JDIMENSION rowgroup_ctr; /* counts row groups output to postprocessor */ + JDIMENSION rowgroups_avail; /* row groups available to postprocessor */ /* Remaining fields are only used in the context case. */ + boolean buffer_full; /* Have we gotten an iMCU row from decoder? */ + /* These are the master pointers to the funny-order pointer lists. */ JSAMPIMAGE xbuffer[2]; /* pointers to weird pointer lists */ int whichptr; /* indicates which pointer set is now in use */ int context_state; /* process_data state machine status */ - JDIMENSION rowgroups_avail; /* row groups available to postprocessor */ JDIMENSION iMCU_row_ctr; /* counts iMCU rows to detect image top/bot */ } my_main_controller; @@ -169,21 +170,22 @@ alloc_funny_pointers (j_decompress_ptr cinfo) /* Get top-level space for component array pointers. * We alloc both arrays with one call to save a few cycles. */ - mainp->xbuffer[0] = (JSAMPIMAGE) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - cinfo->num_components * 2 * SIZEOF(JSAMPARRAY)); + mainp->xbuffer[0] = (JSAMPIMAGE) (*cinfo->mem->alloc_small) + ((j_common_ptr) cinfo, JPOOL_IMAGE, + cinfo->num_components * 2 * SIZEOF(JSAMPARRAY)); mainp->xbuffer[1] = mainp->xbuffer[0] + cinfo->num_components; for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { + if (! compptr->component_needed) + continue; /* skip uninteresting component */ rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) / cinfo->min_DCT_v_scaled_size; /* height of a row group of component */ /* Get space for pointer lists --- M+4 row groups in each list. * We alloc both pointer lists with one call to save a few cycles. */ - xbuf = (JSAMPARRAY) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - 2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW)); + xbuf = (JSAMPARRAY) (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, + JPOOL_IMAGE, 2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW)); xbuf += rgroup; /* want one row group at negative offsets */ mainp->xbuffer[0][ci] = xbuf; xbuf += rgroup * (M + 4); @@ -195,7 +197,7 @@ alloc_funny_pointers (j_decompress_ptr cinfo) LOCAL(void) make_funny_pointers (j_decompress_ptr cinfo) /* Create the funny pointer lists discussed in the comments above. - * The actual workspace is already allocated (in main->buffer), + * The actual workspace is already allocated (in mainp->buffer), * and the space for the pointer lists is allocated too. * This routine just fills in the curiously ordered lists. * This will be repeated at the beginning of each pass. @@ -209,6 +211,8 @@ make_funny_pointers (j_decompress_ptr cinfo) for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { + if (! compptr->component_needed) + continue; /* skip uninteresting component */ rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) / cinfo->min_DCT_v_scaled_size; /* height of a row group of component */ xbuf0 = mainp->xbuffer[0][ci]; @@ -249,6 +253,8 @@ set_wraparound_pointers (j_decompress_ptr cinfo) for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { + if (! compptr->component_needed) + continue; /* skip uninteresting component */ rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) / cinfo->min_DCT_v_scaled_size; /* height of a row group of component */ xbuf0 = mainp->xbuffer[0][ci]; @@ -277,6 +283,8 @@ set_bottom_pointers (j_decompress_ptr cinfo) for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { + if (! compptr->component_needed) + continue; /* skip uninteresting component */ /* Count sample rows in one iMCU row and in one row group */ iMCUheight = compptr->v_samp_factor * compptr->DCT_v_scaled_size; rgroup = iMCUheight / cinfo->min_DCT_v_scaled_size; @@ -317,12 +325,12 @@ start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode) mainp->whichptr = 0; /* Read first iMCU row into xbuffer[0] */ mainp->context_state = CTX_PREPARE_FOR_IMCU; mainp->iMCU_row_ctr = 0; + mainp->buffer_full = FALSE; /* Mark buffer empty */ } else { /* Simple case with no context needed */ mainp->pub.process_data = process_data_simple_main; + mainp->rowgroup_ctr = mainp->rowgroups_avail; /* Mark buffer empty */ } - mainp->buffer_full = FALSE; /* Mark buffer empty */ - mainp->rowgroup_ctr = 0; break; #ifdef QUANT_2PASS_SUPPORTED case JBUF_CRANK_DEST: @@ -332,7 +340,6 @@ start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode) #endif default: ERREXIT(cinfo, JERR_BAD_BUFFER_MODE); - break; } } @@ -343,22 +350,18 @@ start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode) */ METHODDEF(void) -process_data_simple_main (j_decompress_ptr cinfo, - JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, - JDIMENSION out_rows_avail) +process_data_simple_main (j_decompress_ptr cinfo, JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail) { my_main_ptr mainp = (my_main_ptr) cinfo->main; - JDIMENSION rowgroups_avail; /* Read input data if we haven't filled the main buffer yet */ - if (! mainp->buffer_full) { + if (mainp->rowgroup_ctr >= mainp->rowgroups_avail) { if (! (*cinfo->coef->decompress_data) (cinfo, mainp->buffer)) return; /* suspension forced, can do nothing more */ - mainp->buffer_full = TRUE; /* OK, we have an iMCU row to work with */ + mainp->rowgroup_ctr = 0; /* OK, we have an iMCU row to work with */ } - /* There are always min_DCT_scaled_size row groups in an iMCU row. */ - rowgroups_avail = (JDIMENSION) cinfo->min_DCT_v_scaled_size; /* Note: at the bottom of the image, we may pass extra garbage row groups * to the postprocessor. The postprocessor has to check for bottom * of image anyway (at row resolution), so no point in us doing it too. @@ -366,14 +369,8 @@ process_data_simple_main (j_decompress_ptr cinfo, /* Feed the postprocessor */ (*cinfo->post->post_process_data) (cinfo, mainp->buffer, - &mainp->rowgroup_ctr, rowgroups_avail, - output_buf, out_row_ctr, out_rows_avail); - - /* Has postprocessor consumed all the data yet? If so, mark buffer empty */ - if (mainp->rowgroup_ctr >= rowgroups_avail) { - mainp->buffer_full = FALSE; - mainp->rowgroup_ctr = 0; - } + &mainp->rowgroup_ctr, mainp->rowgroups_avail, + output_buf, out_row_ctr, out_rows_avail); } @@ -383,9 +380,8 @@ process_data_simple_main (j_decompress_ptr cinfo, */ METHODDEF(void) -process_data_context_main (j_decompress_ptr cinfo, - JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, - JDIMENSION out_rows_avail) +process_data_context_main (j_decompress_ptr cinfo, JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail) { my_main_ptr mainp = (my_main_ptr) cinfo->main; @@ -457,13 +453,12 @@ process_data_context_main (j_decompress_ptr cinfo, #ifdef QUANT_2PASS_SUPPORTED METHODDEF(void) -process_data_crank_post (j_decompress_ptr cinfo, - JSAMPARRAY output_buf, JDIMENSION *out_row_ctr, - JDIMENSION out_rows_avail) +process_data_crank_post (j_decompress_ptr cinfo, JSAMPARRAY output_buf, + JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail) { (*cinfo->post->post_process_data) (cinfo, (JSAMPIMAGE) NULL, - (JDIMENSION *) NULL, (JDIMENSION) 0, - output_buf, out_row_ctr, out_rows_avail); + (JDIMENSION *) NULL, (JDIMENSION) 0, + output_buf, out_row_ctr, out_rows_avail); } #endif /* QUANT_2PASS_SUPPORTED */ @@ -480,9 +475,8 @@ jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer) int ci, rgroup, ngroups; jpeg_component_info *compptr; - mainp = (my_main_ptr) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, - SIZEOF(my_main_controller)); + mainp = (my_main_ptr) (*cinfo->mem->alloc_small) + ((j_common_ptr) cinfo, JPOOL_IMAGE, SIZEOF(my_main_controller)); cinfo->main = &mainp->pub; mainp->pub.start_pass = start_pass_main; @@ -498,11 +492,15 @@ jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer) alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */ ngroups = cinfo->min_DCT_v_scaled_size + 2; } else { + /* There are always min_DCT_v_scaled_size row groups in an iMCU row. */ ngroups = cinfo->min_DCT_v_scaled_size; + mainp->rowgroups_avail = (JDIMENSION) ngroups; } for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; ci++, compptr++) { + if (! compptr->component_needed) + continue; /* skip uninteresting component */ rgroup = (compptr->v_samp_factor * compptr->DCT_v_scaled_size) / cinfo->min_DCT_v_scaled_size; /* height of a row group of component */ mainp->buffer[ci] = (*cinfo->mem->alloc_sarray) |