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Diffstat (limited to 'media/libjpeg/jdmainct.h')
-rw-r--r-- | media/libjpeg/jdmainct.h | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/media/libjpeg/jdmainct.h b/media/libjpeg/jdmainct.h new file mode 100644 index 0000000000..37b201ca88 --- /dev/null +++ b/media/libjpeg/jdmainct.h @@ -0,0 +1,71 @@ +/* + * jdmainct.h + * + * This file was part of the Independent JPEG Group's software: + * Copyright (C) 1994-1996, Thomas G. Lane. + * For conditions of distribution and use, see the accompanying README.ijg + * file. + */ + +#define JPEG_INTERNALS +#include "jpeglib.h" +#include "jpegcomp.h" + + +/* Private buffer controller object */ + +typedef struct { + struct jpeg_d_main_controller pub; /* public fields */ + + /* 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 */ + + /* Remaining fields are only used in the context case. */ + + /* 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; + +typedef my_main_controller *my_main_ptr; + + +/* context_state values: */ +#define CTX_PREPARE_FOR_IMCU 0 /* need to prepare for MCU row */ +#define CTX_PROCESS_IMCU 1 /* feeding iMCU to postprocessor */ +#define CTX_POSTPONED_ROW 2 /* feeding postponed row group */ + + +LOCAL(void) +set_wraparound_pointers(j_decompress_ptr cinfo) +/* Set up the "wraparound" pointers at top and bottom of the pointer lists. + * This changes the pointer list state from top-of-image to the normal state. + */ +{ + my_main_ptr main_ptr = (my_main_ptr)cinfo->main; + int ci, i, rgroup; + int M = cinfo->_min_DCT_scaled_size; + jpeg_component_info *compptr; + JSAMPARRAY xbuf0, xbuf1; + + for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; + ci++, compptr++) { + rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) / + cinfo->_min_DCT_scaled_size; /* height of a row group of component */ + xbuf0 = main_ptr->xbuffer[0][ci]; + xbuf1 = main_ptr->xbuffer[1][ci]; + for (i = 0; i < rgroup; i++) { + xbuf0[i - rgroup] = xbuf0[rgroup * (M + 1) + i]; + xbuf1[i - rgroup] = xbuf1[rgroup * (M + 1) + i]; + xbuf0[rgroup * (M + 2) + i] = xbuf0[i]; + xbuf1[rgroup * (M + 2) + i] = xbuf1[i]; + } + } +} |