*** empty log message ***

This commit is contained in:
Mike Goslin 2000-11-17 02:25:09 +00:00
parent 6d36e79bfd
commit e3c9d317b1
5 changed files with 127 additions and 5 deletions

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@ -55,6 +55,8 @@ IMGHeaderType img_header_type;
const int img_xsize = config_pnmimagetypes.GetInt("img-xsize", 0);
const int img_ysize = config_pnmimagetypes.GetInt("img-ysize", 0);
const int jpeg_quality = config_pnmimagetypes.GetInt("jpeg-quality", 75);
ConfigureFn(config_pnmimagetypes) {
PNMFileTypePNM::init_type();
PNMFileTypeSGI::init_type();

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@ -26,6 +26,7 @@ extern const double radiance_gamma_correction;
extern const int radiance_brightness_adjustment;
extern const int yuv_xsize;
extern const int yuv_ysize;
extern const int jpeg_quality;
enum IMGHeaderType {
IHT_none,

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@ -42,6 +42,7 @@ public:
class Reader : public PNMReader {
public:
Reader(PNMFileType *type, FILE *file, bool owns_file, string magic_number);
~Reader(void);
virtual int read_data(xel *array, xelval *alpha);

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@ -59,6 +59,15 @@ Reader(PNMFileType *type, FILE *file, bool owns_file, string magic_number) :
_maxval = MAXJSAMPLE;
}
////////////////////////////////////////////////////////////////////
// Function: PNMFileTypeJPG::Reader::Destructor
// Access: Public
// Description:
////////////////////////////////////////////////////////////////////
PNMFileTypeJPG::Reader::
~Reader(void) {
jpeg_destroy_decompress(&_cinfo);
}
////////////////////////////////////////////////////////////////////
// Function: PNMFileTypeJPG::Reader::read_data
@ -133,11 +142,6 @@ read_data(xel *array, xelval *) {
/* We can ignore the return value since suspension is not possible
* with the stdio data source.
/* Step 8: Release JPEG decompression object */
/* This is an important step since it will release a good deal of memory. */
jpeg_destroy_decompress(&_cinfo);
/* At this point you may want to check to see whether any corrupt-data
* warnings occurred (test whether jerr.pub.num_warnings is nonzero).
*/

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@ -53,5 +53,119 @@ write_data(xel *array, xelval *) {
return 0;
}
/* This struct contains the JPEG compression parameters and pointers to
* working space (which is allocated as needed by the JPEG library).
* It is possible to have several such structures, representing multiple
* compression/decompression processes, in existence at once. We refer
* to any one struct (and its associated working data) as a "JPEG object".
*/
struct jpeg_compress_struct cinfo;
/* This struct represents a JPEG error handler. It is declared separately
* because applications often want to supply a specialized error handler
* (see the second half of this file for an example). But here we just
* take the easy way out and use the standard error handler, which will
* print a message on stderr and call exit() if compression fails.
* Note that this struct must live as long as the main JPEG parameter
* struct, to avoid dangling-pointer problems.
*/
struct jpeg_error_mgr jerr;
/* More stuff */
JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */
int row_stride; /* physical row width in image buffer */
/* Step 1: allocate and initialize JPEG compression object */
/* We have to set up the error handler first, in case the initialization
* step fails. (Unlikely, but it could happen if you are out of memory.)
* This routine fills in the contents of struct jerr, and returns jerr's
* address which we place into the link field in cinfo.
*/
cinfo.err = jpeg_std_error(&jerr);
/* Now we can initialize the JPEG compression object. */
jpeg_create_compress(&cinfo);
/* Step 2: specify data destination (eg, a file) */
/* Note: steps 2 and 3 can be done in either order. */
/* Here we use the library-supplied code to send compressed data to a
* stdio stream. You can also write your own code to do something else.
* VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
* requires it in order to write binary files.
*/
jpeg_stdio_dest(&cinfo, _file);
/* Step 3: set parameters for compression */
/* First we supply a description of the input image.
* Four fields of the cinfo struct must be filled in:
*/
cinfo.image_width = _x_size; /* image width and height, in pixels */
cinfo.image_height = _y_size;
if (is_grayscale())
cinfo.input_components = 1;
else
cinfo.input_components = 3;
cinfo.in_color_space = JCS_RGB; /* colorspace of input image */
/* Now use the library's routine to set default compression parameters.
* (You must set at least cinfo.in_color_space before calling this,
* since the defaults depend on the source color space.)
*/
jpeg_set_defaults(&cinfo);
/* Now you can set any non-default parameters you wish to.
* Here we just illustrate the use of quality (quantization table) scaling:
*/
jpeg_set_quality(&cinfo, jpeg_quality, TRUE /* limit to baseline-JPEG values */);
/* Step 4: Start compressor */
/* TRUE ensures that we will write a complete interchange-JPEG file.
* Pass TRUE unless you are very sure of what you're doing.
*/
jpeg_start_compress(&cinfo, TRUE);
/* Step 5: while (scan lines remain to be written) */
/* jpeg_write_scanlines(...); */
/* Here we use the library's state variable cinfo.next_scanline as the
* loop counter, so that we don't have to keep track ourselves.
* To keep things simple, we pass one scanline per call; you can pass
* more if you wish, though.
*/
row_stride = _x_size * cinfo.input_components; /* JSAMPLEs per row in image_buffer */
int x = 0;
JSAMPROW row = new JSAMPLE[row_stride];
while (cinfo.next_scanline < cinfo.image_height) {
/* jpeg_write_scanlines expects an array of pointers to scanlines.
* Here the array is only one element long, but you could pass
* more than one scanline at a time if that's more convenient.
*/
for (int i = 0; i < row_stride; i += cinfo.input_components) {
if (cinfo.input_components == 1) {
row[i] = (JSAMPLE)(MAXJSAMPLE * PPM_GETB(array[x])/_maxval);
} else {
row[i] = (JSAMPLE)(MAXJSAMPLE * PPM_GETR(array[x])/_maxval);
row[i+1] = (JSAMPLE)(MAXJSAMPLE * PPM_GETG(array[x])/_maxval);
row[i+2] = (JSAMPLE)(MAXJSAMPLE * PPM_GETB(array[x])/_maxval);
}
x++;
}
//row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride];
//(void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
row_pointer[0] = row;
(void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
}
delete row;
/* Step 6: Finish compression */
jpeg_finish_compress(&cinfo);
/* Step 7: release JPEG compression object */
/* This is an important step since it will release a good deal of memory. */
jpeg_destroy_compress(&cinfo);
return _y_size;
}