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The Independent JPEG Group's JPEG software v7

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This commit is contained in:
Guido Vollbeding
2009-06-27 00:00:00 +00:00
committed by DRC
parent 1e247ac854
commit 5996a25e2f
143 changed files with 56935 additions and 12882 deletions
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13
jdinput.c
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@@ -2,13 +2,14 @@
* jdinput.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2002-2009 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.
*
* This file contains input control logic for the JPEG decompressor.
* These routines are concerned with controlling the decompressor's input
* processing (marker reading and coefficient decoding). The actual input
* reading is done in jdmarker.c, jdhuff.c, and jdphuff.c.
* reading is done in jdmarker.c, jdhuff.c, and jdarith.c.
*/
#define JPEG_INTERNALS
@@ -74,12 +75,14 @@ initial_setup (j_decompress_ptr cinfo)
* In the full decompressor, this will be overridden by jdmaster.c;
* but in the transcoder, jdmaster.c is not used, so we must do it here.
*/
cinfo->min_DCT_scaled_size = DCTSIZE;
cinfo->min_DCT_h_scaled_size = DCTSIZE;
cinfo->min_DCT_v_scaled_size = DCTSIZE;
/* Compute dimensions of components */
for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
ci++, compptr++) {
compptr->DCT_scaled_size = DCTSIZE;
compptr->DCT_h_scaled_size = DCTSIZE;
compptr->DCT_v_scaled_size = DCTSIZE;
/* Size in DCT blocks */
compptr->width_in_blocks = (JDIMENSION)
jdiv_round_up((long) cinfo->image_width * (long) compptr->h_samp_factor,
@@ -138,7 +141,7 @@ per_scan_setup (j_decompress_ptr cinfo)
compptr->MCU_width = 1;
compptr->MCU_height = 1;
compptr->MCU_blocks = 1;
compptr->MCU_sample_width = compptr->DCT_scaled_size;
compptr->MCU_sample_width = compptr->DCT_h_scaled_size;
compptr->last_col_width = 1;
/* For noninterleaved scans, it is convenient to define last_row_height
* as the number of block rows present in the last iMCU row.
@@ -174,7 +177,7 @@ per_scan_setup (j_decompress_ptr cinfo)
compptr->MCU_width = compptr->h_samp_factor;
compptr->MCU_height = compptr->v_samp_factor;
compptr->MCU_blocks = compptr->MCU_width * compptr->MCU_height;
compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_scaled_size;
compptr->MCU_sample_width = compptr->MCU_width * compptr->DCT_h_scaled_size;
/* Figure number of non-dummy blocks in last MCU column & row */
tmp = (int) (compptr->width_in_blocks % compptr->MCU_width);
if (tmp == 0) tmp = compptr->MCU_width;