diff options
Diffstat (limited to 'jpeg/transupp.h')
| -rw-r--r-- | jpeg/transupp.h | 213 |
1 files changed, 0 insertions, 213 deletions
diff --git a/jpeg/transupp.h b/jpeg/transupp.h deleted file mode 100644 index 9aa0af3..0000000 --- a/jpeg/transupp.h +++ /dev/null @@ -1,213 +0,0 @@ -/* - * transupp.h - * - * Copyright (C) 1997-2011, Thomas G. Lane, 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 declarations for image transformation routines and - * other utility code used by the jpegtran sample application. These are - * NOT part of the core JPEG library. But we keep these routines separate - * from jpegtran.c to ease the task of maintaining jpegtran-like programs - * that have other user interfaces. - * - * NOTE: all the routines declared here have very specific requirements - * about when they are to be executed during the reading and writing of the - * source and destination files. See the comments in transupp.c, or see - * jpegtran.c for an example of correct usage. - */ - -/* If you happen not to want the image transform support, disable it here */ -#ifndef TRANSFORMS_SUPPORTED -#define TRANSFORMS_SUPPORTED 1 /* 0 disables transform code */ -#endif - -/* - * Although rotating and flipping data expressed as DCT coefficients is not - * hard, there is an asymmetry in the JPEG format specification for images - * whose dimensions aren't multiples of the iMCU size. The right and bottom - * image edges are padded out to the next iMCU boundary with junk data; but - * no padding is possible at the top and left edges. If we were to flip - * the whole image including the pad data, then pad garbage would become - * visible at the top and/or left, and real pixels would disappear into the - * pad margins --- perhaps permanently, since encoders & decoders may not - * bother to preserve DCT blocks that appear to be completely outside the - * nominal image area. So, we have to exclude any partial iMCUs from the - * basic transformation. - * - * Transpose is the only transformation that can handle partial iMCUs at the - * right and bottom edges completely cleanly. flip_h can flip partial iMCUs - * at the bottom, but leaves any partial iMCUs at the right edge untouched. - * Similarly flip_v leaves any partial iMCUs at the bottom edge untouched. - * The other transforms are defined as combinations of these basic transforms - * and process edge blocks in a way that preserves the equivalence. - * - * The "trim" option causes untransformable partial iMCUs to be dropped; - * this is not strictly lossless, but it usually gives the best-looking - * result for odd-size images. Note that when this option is active, - * the expected mathematical equivalences between the transforms may not hold. - * (For example, -rot 270 -trim trims only the bottom edge, but -rot 90 -trim - * followed by -rot 180 -trim trims both edges.) - * - * We also offer a lossless-crop option, which discards data outside a given - * image region but losslessly preserves what is inside. Like the rotate and - * flip transforms, lossless crop is restricted by the JPEG format: the upper - * left corner of the selected region must fall on an iMCU boundary. If this - * does not hold for the given crop parameters, we silently move the upper left - * corner up and/or left to make it so, simultaneously increasing the region - * dimensions to keep the lower right crop corner unchanged. (Thus, the - * output image covers at least the requested region, but may cover more.) - * The adjustment of the region dimensions may be optionally disabled. - * - * We also provide a lossless-resize option, which is kind of a lossless-crop - * operation in the DCT coefficient block domain - it discards higher-order - * coefficients and losslessly preserves lower-order coefficients of a - * sub-block. - * - * Rotate/flip transform, resize, and crop can be requested together in a - * single invocation. The crop is applied last --- that is, the crop region - * is specified in terms of the destination image after transform/resize. - * - * We also offer a "force to grayscale" option, which simply discards the - * chrominance channels of a YCbCr image. This is lossless in the sense that - * the luminance channel is preserved exactly. It's not the same kind of - * thing as the rotate/flip transformations, but it's convenient to handle it - * as part of this package, mainly because the transformation routines have to - * be aware of the option to know how many components to work on. - */ - - -/* Short forms of external names for systems with brain-damaged linkers. */ - -#ifdef NEED_SHORT_EXTERNAL_NAMES -#define jtransform_parse_crop_spec jTrParCrop -#define jtransform_request_workspace jTrRequest -#define jtransform_adjust_parameters jTrAdjust -#define jtransform_execute_transform jTrExec -#define jtransform_perfect_transform jTrPerfect -#define jcopy_markers_setup jCMrkSetup -#define jcopy_markers_execute jCMrkExec -#endif /* NEED_SHORT_EXTERNAL_NAMES */ - - -/* - * Codes for supported types of image transformations. - */ - -typedef enum { - JXFORM_NONE, /* no transformation */ - JXFORM_FLIP_H, /* horizontal flip */ - JXFORM_FLIP_V, /* vertical flip */ - JXFORM_TRANSPOSE, /* transpose across UL-to-LR axis */ - JXFORM_TRANSVERSE, /* transpose across UR-to-LL axis */ - JXFORM_ROT_90, /* 90-degree clockwise rotation */ - JXFORM_ROT_180, /* 180-degree rotation */ - JXFORM_ROT_270 /* 270-degree clockwise (or 90 ccw) */ -} JXFORM_CODE; - -/* - * Codes for crop parameters, which can individually be unspecified, - * positive or negative for xoffset or yoffset, - * positive or forced for width or height. - */ - -typedef enum { - JCROP_UNSET, - JCROP_POS, - JCROP_NEG, - JCROP_FORCE -} JCROP_CODE; - -/* - * Transform parameters struct. - * NB: application must not change any elements of this struct after - * calling jtransform_request_workspace. - */ - -typedef struct { - /* Options: set by caller */ - JXFORM_CODE transform; /* image transform operator */ - boolean perfect; /* if TRUE, fail if partial MCUs are requested */ - boolean trim; /* if TRUE, trim partial MCUs as needed */ - boolean force_grayscale; /* if TRUE, convert color image to grayscale */ - boolean crop; /* if TRUE, crop source image */ - - /* Crop parameters: application need not set these unless crop is TRUE. - * These can be filled in by jtransform_parse_crop_spec(). - */ - JDIMENSION crop_width; /* Width of selected region */ - JCROP_CODE crop_width_set; /* (forced disables adjustment) */ - JDIMENSION crop_height; /* Height of selected region */ - JCROP_CODE crop_height_set; /* (forced disables adjustment) */ - JDIMENSION crop_xoffset; /* X offset of selected region */ - JCROP_CODE crop_xoffset_set; /* (negative measures from right edge) */ - JDIMENSION crop_yoffset; /* Y offset of selected region */ - JCROP_CODE crop_yoffset_set; /* (negative measures from bottom edge) */ - - /* Internal workspace: caller should not touch these */ - int num_components; /* # of components in workspace */ - jvirt_barray_ptr * workspace_coef_arrays; /* workspace for transformations */ - JDIMENSION output_width; /* cropped destination dimensions */ - JDIMENSION output_height; - JDIMENSION x_crop_offset; /* destination crop offsets measured in iMCUs */ - JDIMENSION y_crop_offset; - int iMCU_sample_width; /* destination iMCU size */ - int iMCU_sample_height; -} jpeg_transform_info; - - -#if TRANSFORMS_SUPPORTED - -/* Parse a crop specification (written in X11 geometry style) */ -EXTERN(boolean) jtransform_parse_crop_spec - JPP((jpeg_transform_info *info, const char *spec)); -/* Request any required workspace */ -EXTERN(boolean) jtransform_request_workspace - JPP((j_decompress_ptr srcinfo, jpeg_transform_info *info)); -/* Adjust output image parameters */ -EXTERN(jvirt_barray_ptr *) jtransform_adjust_parameters - JPP((j_decompress_ptr srcinfo, j_compress_ptr dstinfo, - jvirt_barray_ptr *src_coef_arrays, - jpeg_transform_info *info)); -/* Execute the actual transformation, if any */ -EXTERN(void) jtransform_execute_transform - JPP((j_decompress_ptr srcinfo, j_compress_ptr dstinfo, - jvirt_barray_ptr *src_coef_arrays, - jpeg_transform_info *info)); -/* Determine whether lossless transformation is perfectly - * possible for a specified image and transformation. - */ -EXTERN(boolean) jtransform_perfect_transform - JPP((JDIMENSION image_width, JDIMENSION image_height, - int MCU_width, int MCU_height, - JXFORM_CODE transform)); - -/* jtransform_execute_transform used to be called - * jtransform_execute_transformation, but some compilers complain about - * routine names that long. This macro is here to avoid breaking any - * old source code that uses the original name... - */ -#define jtransform_execute_transformation jtransform_execute_transform - -#endif /* TRANSFORMS_SUPPORTED */ - - -/* - * Support for copying optional markers from source to destination file. - */ - -typedef enum { - JCOPYOPT_NONE, /* copy no optional markers */ - JCOPYOPT_COMMENTS, /* copy only comment (COM) markers */ - JCOPYOPT_ALL /* copy all optional markers */ -} JCOPY_OPTION; - -#define JCOPYOPT_DEFAULT JCOPYOPT_COMMENTS /* recommended default */ - -/* Setup decompression object to save desired markers in memory */ -EXTERN(void) jcopy_markers_setup - JPP((j_decompress_ptr srcinfo, JCOPY_OPTION option)); -/* Copy markers saved in the given source object to the destination object */ -EXTERN(void) jcopy_markers_execute - JPP((j_decompress_ptr srcinfo, j_compress_ptr dstinfo, - JCOPY_OPTION option)); |