-/*
- * ERROR HANDLING:
- *
- * The JPEG library's standard error handler (jerror.c) is divided into
- * several "methods" which you can override individually. This lets you
- * adjust the behavior without duplicating a lot of code, which you might
- * have to update with each future release.
- *
- * Our example here shows how to override the "error_exit" method so that
- * control is returned to the library's caller when a fatal error occurs,
- * rather than calling exit() as the standard error_exit method does.
- *
- * We use C's setjmp/longjmp facility to return control. This means that the
- * routine which calls the JPEG library must first execute a setjmp() call to
- * establish the return point. We want the replacement error_exit to do a
- * longjmp(). But we need to make the setjmp buffer accessible to the
- * error_exit routine. To do this, we make a private extension of the
- * standard JPEG error handler object. (If we were using C++, we'd say we
- * were making a subclass of the regular error handler.)
- *
- * Here's the extended error handler struct:
- */
+ /* 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.
+ */
+ // if ((outfile = fopen(filename, "wb")) == NULL) {
+ // fprintf(stderr, "can't open %s\n", filename);
+ // exit(1);
+ //
+ // }
+ jpeg_stdio_dest(&cinfo, fp);
+
+ /* 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 = image_width;/* image width and height, in pixels */
+ cinfo.image_height = image_height;
+ cinfo.input_components = 3; /* # of color components per pixel */
+ 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, 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 = image_width * 3;/* JSAMPLEs per row in image_buffer */
+
+ 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.
+ */
+ row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride];
+
+ (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
+ }
+
+ /* Step 6: Finish compression */
+
+ jpeg_finish_compress(&cinfo);
+
+ /* After finish_compress, we can close the output file. */
+
+ // fclose(fp); --> the caller will close (multiframe treatement)
+
+ /* Step 7: release JPEG compression object */
+
+ /* This is an important step since it will release a good deal of memory. */
+ jpeg_destroy_compress(&cinfo);
+
+ /* And we're done! */
+
+ return true;
+}