| Index: third_party/libjpeg_turbo/jdatadst.c
|
| ===================================================================
|
| --- third_party/libjpeg_turbo/jdatadst.c (revision 0)
|
| +++ third_party/libjpeg_turbo/jdatadst.c (revision 0)
|
| @@ -0,0 +1,151 @@
|
| +/*
|
| + * jdatadst.c
|
| + *
|
| + * Copyright (C) 1994-1996, Thomas G. Lane.
|
| + * 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 compression data destination routines for the case of
|
| + * emitting JPEG data to a file (or any stdio stream). While these routines
|
| + * are sufficient for most applications, some will want to use a different
|
| + * destination manager.
|
| + * IMPORTANT: we assume that fwrite() will correctly transcribe an array of
|
| + * JOCTETs into 8-bit-wide elements on external storage. If char is wider
|
| + * than 8 bits on your machine, you may need to do some tweaking.
|
| + */
|
| +
|
| +/* this is not a core library module, so it doesn't define JPEG_INTERNALS */
|
| +#include "jinclude.h"
|
| +#include "jpeglib.h"
|
| +#include "jerror.h"
|
| +
|
| +
|
| +/* Expanded data destination object for stdio output */
|
| +
|
| +typedef struct {
|
| + struct jpeg_destination_mgr pub; /* public fields */
|
| +
|
| + FILE * outfile; /* target stream */
|
| + JOCTET * buffer; /* start of buffer */
|
| +} my_destination_mgr;
|
| +
|
| +typedef my_destination_mgr * my_dest_ptr;
|
| +
|
| +#define OUTPUT_BUF_SIZE 4096 /* choose an efficiently fwrite'able size */
|
| +
|
| +
|
| +/*
|
| + * Initialize destination --- called by jpeg_start_compress
|
| + * before any data is actually written.
|
| + */
|
| +
|
| +METHODDEF(void)
|
| +init_destination (j_compress_ptr cinfo)
|
| +{
|
| + my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
|
| +
|
| + /* Allocate the output buffer --- it will be released when done with image */
|
| + dest->buffer = (JOCTET *)
|
| + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
|
| + OUTPUT_BUF_SIZE * SIZEOF(JOCTET));
|
| +
|
| + dest->pub.next_output_byte = dest->buffer;
|
| + dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
|
| +}
|
| +
|
| +
|
| +/*
|
| + * Empty the output buffer --- called whenever buffer fills up.
|
| + *
|
| + * In typical applications, this should write the entire output buffer
|
| + * (ignoring the current state of next_output_byte & free_in_buffer),
|
| + * reset the pointer & count to the start of the buffer, and return TRUE
|
| + * indicating that the buffer has been dumped.
|
| + *
|
| + * In applications that need to be able to suspend compression due to output
|
| + * overrun, a FALSE return indicates that the buffer cannot be emptied now.
|
| + * In this situation, the compressor will return to its caller (possibly with
|
| + * an indication that it has not accepted all the supplied scanlines). The
|
| + * application should resume compression after it has made more room in the
|
| + * output buffer. Note that there are substantial restrictions on the use of
|
| + * suspension --- see the documentation.
|
| + *
|
| + * When suspending, the compressor will back up to a convenient restart point
|
| + * (typically the start of the current MCU). next_output_byte & free_in_buffer
|
| + * indicate where the restart point will be if the current call returns FALSE.
|
| + * Data beyond this point will be regenerated after resumption, so do not
|
| + * write it out when emptying the buffer externally.
|
| + */
|
| +
|
| +METHODDEF(boolean)
|
| +empty_output_buffer (j_compress_ptr cinfo)
|
| +{
|
| + my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
|
| +
|
| + if (JFWRITE(dest->outfile, dest->buffer, OUTPUT_BUF_SIZE) !=
|
| + (size_t) OUTPUT_BUF_SIZE)
|
| + ERREXIT(cinfo, JERR_FILE_WRITE);
|
| +
|
| + dest->pub.next_output_byte = dest->buffer;
|
| + dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
|
| +
|
| + return TRUE;
|
| +}
|
| +
|
| +
|
| +/*
|
| + * Terminate destination --- called by jpeg_finish_compress
|
| + * after all data has been written. Usually needs to flush buffer.
|
| + *
|
| + * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
|
| + * application must deal with any cleanup that should happen even
|
| + * for error exit.
|
| + */
|
| +
|
| +METHODDEF(void)
|
| +term_destination (j_compress_ptr cinfo)
|
| +{
|
| + my_dest_ptr dest = (my_dest_ptr) cinfo->dest;
|
| + size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
|
| +
|
| + /* Write any data remaining in the buffer */
|
| + if (datacount > 0) {
|
| + if (JFWRITE(dest->outfile, dest->buffer, datacount) != datacount)
|
| + ERREXIT(cinfo, JERR_FILE_WRITE);
|
| + }
|
| + fflush(dest->outfile);
|
| + /* Make sure we wrote the output file OK */
|
| + if (ferror(dest->outfile))
|
| + ERREXIT(cinfo, JERR_FILE_WRITE);
|
| +}
|
| +
|
| +
|
| +/*
|
| + * Prepare for output to a stdio stream.
|
| + * The caller must have already opened the stream, and is responsible
|
| + * for closing it after finishing compression.
|
| + */
|
| +
|
| +GLOBAL(void)
|
| +jpeg_stdio_dest (j_compress_ptr cinfo, FILE * outfile)
|
| +{
|
| + my_dest_ptr dest;
|
| +
|
| + /* The destination object is made permanent so that multiple JPEG images
|
| + * can be written to the same file without re-executing jpeg_stdio_dest.
|
| + * This makes it dangerous to use this manager and a different destination
|
| + * manager serially with the same JPEG object, because their private object
|
| + * sizes may be different. Caveat programmer.
|
| + */
|
| + if (cinfo->dest == NULL) { /* first time for this JPEG object? */
|
| + cinfo->dest = (struct jpeg_destination_mgr *)
|
| + (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
|
| + SIZEOF(my_destination_mgr));
|
| + }
|
| +
|
| + dest = (my_dest_ptr) cinfo->dest;
|
| + dest->pub.init_destination = init_destination;
|
| + dest->pub.empty_output_buffer = empty_output_buffer;
|
| + dest->pub.term_destination = term_destination;
|
| + dest->outfile = outfile;
|
| +}
|
|
|