diff options
Diffstat (limited to 'jpeg/jdtrans.c')
-rw-r--r-- | jpeg/jdtrans.c | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/jpeg/jdtrans.c b/jpeg/jdtrans.c deleted file mode 100644 index 22dd47f..0000000 --- a/jpeg/jdtrans.c +++ /dev/null @@ -1,140 +0,0 @@ -/* - * jdtrans.c - * - * Copyright (C) 1995-1997, Thomas G. Lane. - * Modified 2000-2009 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 library routines for transcoding decompression, - * that is, reading raw DCT coefficient arrays from an input JPEG file. - * The routines in jdapimin.c will also be needed by a transcoder. - */ - -#define JPEG_INTERNALS -#include "jinclude.h" -#include "jpeglib.h" - - -/* Forward declarations */ -LOCAL(void) transdecode_master_selection JPP((j_decompress_ptr cinfo)); - - -/* - * Read the coefficient arrays from a JPEG file. - * jpeg_read_header must be completed before calling this. - * - * The entire image is read into a set of virtual coefficient-block arrays, - * one per component. The return value is a pointer to the array of - * virtual-array descriptors. These can be manipulated directly via the - * JPEG memory manager, or handed off to jpeg_write_coefficients(). - * To release the memory occupied by the virtual arrays, call - * jpeg_finish_decompress() when done with the data. - * - * An alternative usage is to simply obtain access to the coefficient arrays - * during a buffered-image-mode decompression operation. This is allowed - * after any jpeg_finish_output() call. The arrays can be accessed until - * jpeg_finish_decompress() is called. (Note that any call to the library - * may reposition the arrays, so don't rely on access_virt_barray() results - * to stay valid across library calls.) - * - * Returns NULL if suspended. This case need be checked only if - * a suspending data source is used. - */ - -GLOBAL(jvirt_barray_ptr *) -jpeg_read_coefficients (j_decompress_ptr cinfo) -{ - if (cinfo->global_state == DSTATE_READY) { - /* First call: initialize active modules */ - transdecode_master_selection(cinfo); - cinfo->global_state = DSTATE_RDCOEFS; - } - if (cinfo->global_state == DSTATE_RDCOEFS) { - /* Absorb whole file into the coef buffer */ - for (;;) { - int retcode; - /* Call progress monitor hook if present */ - if (cinfo->progress != NULL) - (*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo); - /* Absorb some more input */ - retcode = (*cinfo->inputctl->consume_input) (cinfo); - if (retcode == JPEG_SUSPENDED) - return NULL; - if (retcode == JPEG_REACHED_EOI) - break; - /* Advance progress counter if appropriate */ - if (cinfo->progress != NULL && - (retcode == JPEG_ROW_COMPLETED || retcode == JPEG_REACHED_SOS)) { - if (++cinfo->progress->pass_counter >= cinfo->progress->pass_limit) { - /* startup underestimated number of scans; ratchet up one scan */ - cinfo->progress->pass_limit += (long) cinfo->total_iMCU_rows; - } - } - } - /* Set state so that jpeg_finish_decompress does the right thing */ - cinfo->global_state = DSTATE_STOPPING; - } - /* At this point we should be in state DSTATE_STOPPING if being used - * standalone, or in state DSTATE_BUFIMAGE if being invoked to get access - * to the coefficients during a full buffered-image-mode decompression. - */ - if ((cinfo->global_state == DSTATE_STOPPING || - cinfo->global_state == DSTATE_BUFIMAGE) && cinfo->buffered_image) { - return cinfo->coef->coef_arrays; - } - /* Oops, improper usage */ - ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state); - return NULL; /* keep compiler happy */ -} - - -/* - * Master selection of decompression modules for transcoding. - * This substitutes for jdmaster.c's initialization of the full decompressor. - */ - -LOCAL(void) -transdecode_master_selection (j_decompress_ptr cinfo) -{ - /* This is effectively a buffered-image operation. */ - cinfo->buffered_image = TRUE; - - /* Compute output image dimensions and related values. */ - jpeg_core_output_dimensions(cinfo); - - /* Entropy decoding: either Huffman or arithmetic coding. */ - if (cinfo->arith_code) - jinit_arith_decoder(cinfo); - else { - jinit_huff_decoder(cinfo); - } - - /* Always get a full-image coefficient buffer. */ - jinit_d_coef_controller(cinfo, TRUE); - - /* We can now tell the memory manager to allocate virtual arrays. */ - (*cinfo->mem->realize_virt_arrays) ((j_common_ptr) cinfo); - - /* Initialize input side of decompressor to consume first scan. */ - (*cinfo->inputctl->start_input_pass) (cinfo); - - /* Initialize progress monitoring. */ - if (cinfo->progress != NULL) { - int nscans; - /* Estimate number of scans to set pass_limit. */ - if (cinfo->progressive_mode) { - /* Arbitrarily estimate 2 interleaved DC scans + 3 AC scans/component. */ - nscans = 2 + 3 * cinfo->num_components; - } else if (cinfo->inputctl->has_multiple_scans) { - /* For a nonprogressive multiscan file, estimate 1 scan per component. */ - nscans = cinfo->num_components; - } else { - nscans = 1; - } - cinfo->progress->pass_counter = 0L; - cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows * nscans; - cinfo->progress->completed_passes = 0; - cinfo->progress->total_passes = 1; - } -} |