/*
* jdmerge.h
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1994-1996, Thomas G. Lane.
* libjpeg-turbo Modifications:
* Copyright (C) 2020, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*/
#define JPEG_INTERNALS
#include "jpeglib.h"
#ifdef UPSAMPLE_MERGING_SUPPORTED
/* Private subobject */
typedef struct {
struct jpeg_upsampler pub; /* public fields */
/* Pointer to routine to do actual upsampling/conversion of one row group */
void (*upmethod) (j_decompress_ptr cinfo, JSAMPIMAGE input_buf,
JDIMENSION in_row_group_ctr, JSAMPARRAY output_buf);
/* Private state for YCC->RGB conversion */
int *Cr_r_tab; /* => table for Cr to R conversion */
int *Cb_b_tab; /* => table for Cb to B conversion */
JLONG *Cr_g_tab; /* => table for Cr to G conversion */
JLONG *Cb_g_tab; /* => table for Cb to G conversion */
/* For 2:1 vertical sampling, we produce two output rows at a time.
* We need a "spare" row buffer to hold the second output row if the
* application provides just a one-row buffer; we also use the spare
* to discard the dummy last row if the image height is odd.
*/
JSAMPROW spare_row;
boolean spare_full; /* T if spare buffer is occupied */
JDIMENSION out_row_width; /* samples per output row */
JDIMENSION rows_to_go; /* counts rows remaining in image */
} my_merged_upsampler;
typedef my_merged_upsampler *my_merged_upsample_ptr;
#endif /* UPSAMPLE_MERGING_SUPPORTED */