Branch
Hash :
e69dd40c
Author :
Date :
2024-01-23T13:26:41
Reorganize source to make things easier to find
- Move all libjpeg documentation, except for README.ijg, into the doc/
subdirectory.
- Move the TurboJPEG C API documentation from doc/html/ into
doc/turbojpeg/.
- Move all C source code and headers into a src/ subdirectory.
- Move turbojpeg-jni.c into the java/ subdirectory.
Referring to #226, there is no ideal solution to this problem. A
semantically ideal solution would have involved placing all source code,
including the SIMD and Java source code, under src/ (or perhaps placing
C library source code under lib/ and C test program source code under
test/), all header files under include/, and all documentation under
doc/. However:
- To me it makes more sense to have separate top-level directories for
each language, since the SIMD extensions and the Java API are
technically optional features. src/ now contains only the code that
is relevant to the core C API libraries and associated programs.
- I didn't want to bury the java/ and simd/ directories or add a level
of depth to them, since both directories already contain source code
that is 3-4 levels deep.
- I would prefer not to separate the header files from the C source
code, because:
1. It would be disruptive. libjpeg and libjpeg-turbo have
historically placed C source code and headers in the same
directory, and people who are familiar with both projects (self
included) are used to looking for the headers in the same directory
as the C source code.
2. In terms of how the headers are used internally in libjpeg-turbo,
the distinction between public and private headers is a bit fuzzy.
- It didn't make sense to separate the test source code from the library
source code, since there is not a clear distinction in some cases.
(For instance, the IJG image I/O functions are used by cjpeg and djpeg
as well as by the TurboJPEG API.)
This solution is minimally disruptive, since it keeps all C source code
and headers together and keeps java/ and simd/ as top-level directories.
It is a bit awkward, because java/ and simd/ technically contain source
code, even though they are not under src/. However, other solutions
would have been more awkward for different reasons.
Closes #226
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/*
* jlossls.h
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1998, Thomas G. Lane.
* Lossless JPEG Modifications:
* Copyright (C) 1999, Ken Murchison.
* libjpeg-turbo Modifications:
* Copyright (C) 2022, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* This include file contains common declarations for the lossless JPEG
* codec modules.
*/
#ifndef JLOSSLS_H
#define JLOSSLS_H
#if defined(C_LOSSLESS_SUPPORTED) || defined(D_LOSSLESS_SUPPORTED)
#define JPEG_INTERNALS
#include "jpeglib.h"
#include "jsamplecomp.h"
#define ALLOC_DARRAY(pool_id, diffsperrow, numrows) \
(JDIFFARRAY)(*cinfo->mem->alloc_sarray) \
((j_common_ptr)cinfo, pool_id, \
(diffsperrow) * sizeof(JDIFF) / sizeof(_JSAMPLE), numrows)
/*
* Table H.1: Predictors for lossless coding.
*/
#define PREDICTOR1 Ra
#define PREDICTOR2 Rb
#define PREDICTOR3 Rc
#define PREDICTOR4 (int)((JLONG)Ra + (JLONG)Rb - (JLONG)Rc)
#define PREDICTOR5 (int)((JLONG)Ra + RIGHT_SHIFT((JLONG)Rb - (JLONG)Rc, 1))
#define PREDICTOR6 (int)((JLONG)Rb + RIGHT_SHIFT((JLONG)Ra - (JLONG)Rc, 1))
#define PREDICTOR7 (int)RIGHT_SHIFT((JLONG)Ra + (JLONG)Rb, 1)
#endif
#ifdef C_LOSSLESS_SUPPORTED
typedef void (*predict_difference_method_ptr) (j_compress_ptr cinfo, int ci,
_JSAMPROW input_buf,
_JSAMPROW prev_row,
JDIFFROW diff_buf,
JDIMENSION width);
/* Lossless compressor */
typedef struct {
struct jpeg_forward_dct pub; /* public fields */
/* It is useful to allow each component to have a separate diff method. */
predict_difference_method_ptr predict_difference[MAX_COMPONENTS];
/* MCU rows left in the restart interval for each component */
unsigned int restart_rows_to_go[MAX_COMPONENTS];
/* Sample scaling */
void (*scaler_scale) (j_compress_ptr cinfo, _JSAMPROW input_buf,
_JSAMPROW output_buf, JDIMENSION width);
} jpeg_lossless_compressor;
typedef jpeg_lossless_compressor *lossless_comp_ptr;
#endif /* C_LOSSLESS_SUPPORTED */
#ifdef D_LOSSLESS_SUPPORTED
typedef void (*predict_undifference_method_ptr) (j_decompress_ptr cinfo,
int comp_index,
JDIFFROW diff_buf,
JDIFFROW prev_row,
JDIFFROW undiff_buf,
JDIMENSION width);
/* Lossless decompressor */
typedef struct {
struct jpeg_inverse_dct pub; /* public fields */
/* It is useful to allow each component to have a separate undiff method. */
predict_undifference_method_ptr predict_undifference[MAX_COMPONENTS];
/* Sample scaling */
void (*scaler_scale) (j_decompress_ptr cinfo, JDIFFROW diff_buf,
_JSAMPROW output_buf, JDIMENSION width);
} jpeg_lossless_decompressor;
typedef jpeg_lossless_decompressor *lossless_decomp_ptr;
#endif /* D_LOSSLESS_SUPPORTED */
#endif /* JLOSSLS_H */