esp32-camera/conversions/libjpeg.c

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "stdint.h"

/*
 * Include file for users of JPEG library.
 * You will need to have included system headers that define at least
 * the typedefs FILE and size_t before you can include jpeglib.h.
 * (stdio.h is sufficient on ANSI-conforming systems.)
 * You may also wish to include "jerror.h".
 */

#include "jpeg-9a/jpeglib.h"
#include "include/libjpeg.h"

/*
 * <setjmp.h> is used for the optional error recovery mechanism shown in
 * the second part of the example.
 */

#include <setjmp.h>


/******************** JPEG COMPRESSION SAMPLE INTERFACE *******************/

/* This half of the example shows how to feed data into the JPEG compressor.
 * We present a minimal version that does not worry about refinements such
 * as error recovery (the JPEG code will just exit() if it gets an error).
 */


_Bool libjpeg_encode(const uint8_t *in_buffer, color_space_t src_type, int image_width, int image_height, int quality, uint8_t **outbuffer, uint32_t *outsize)
{
  /* 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. */
  jpeg_mem_dest(&cinfo, outbuffer, (unsigned long *)outsize);

  /* 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 */
  if(COLOR_TYPE_RGB888 == src_type){
    cinfo.in_color_space = JCS_RGB; 	/* colorspace of input image */
  } else if(COLOR_TYPE_RGB565 == src_type){
    cinfo.in_color_space = JCS_RGB; 	/* colorspace of input image */
  } else if(COLOR_TYPE_YUV422 == src_type){
    cinfo.in_color_space = JCS_YCbCr; 	/* colorspace of input image */
  } else {
    printf("Unsupported source type\n");
    return 0;
  }
  /* 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.
   */
  if (COLOR_TYPE_RGB888 == src_type) {
        row_stride = image_width * 3;   /* JSAMPLEs per row in 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] = (uint8_t *)&in_buffer[cinfo.next_scanline * row_stride];
            (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
        }
    } else if (COLOR_TYPE_YUV422 == src_type) {
        row_stride = cinfo.image_width * cinfo.input_components;
        row_pointer[0] = (JSAMPROW)(*cinfo.mem->alloc_sarray)
                         ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);

        while (cinfo.next_scanline < cinfo.image_height) {
            uint8_t *out = row_pointer[0];
            uint8_t *in = (uint8_t *)&in_buffer[cinfo.next_scanline * cinfo.image_width * 2];
            uint32_t j = 0;
            for (size_t i = 0; i < cinfo.image_width * 2; i += 4) {
                out[j++] = in[i]; //y0
                out[j++] = in[i + 1]; //u0
                out[j++] = in[i + 3]; //v0

                out[j++] = in[i + 2]; //y1
                out[j++] = in[i + 1]; //u1
                out[j++] = in[i + 3]; //v1
            }
            (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
        }
    } else if (COLOR_TYPE_RGB565 == src_type) {
        row_stride = cinfo.image_width * cinfo.input_components;
        row_pointer[0] = (JSAMPROW)(*cinfo.mem->alloc_sarray)
                         ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);

        while (cinfo.next_scanline < cinfo.image_height) {
            uint8_t *out = row_pointer[0];
            uint8_t *in = (uint8_t *)&in_buffer[cinfo.next_scanline * cinfo.image_width * 2];
            for (size_t i = 0; i < cinfo.image_width * 2; i += 2) {
              uint16_t *psrcdot = (uint16_t*)&in[i];
#if ENCODE_LITTLE_ENDIAN
              //src little-endian
              *out++ = (unsigned char)(((*psrcdot) >> 11) << 3);
              *out++ = (unsigned char)(((*psrcdot) >> 5 ) << 2);
              *out++ = (unsigned char)(((*psrcdot) >> 0 ) << 3);
#else
              //src big-endian
              *out++ = (unsigned char)(((*psrcdot) >> 3 ) << 3);
              *out++ = (unsigned char)(((*psrcdot) << 5 ) | ((*psrcdot)&0xe0)>>11);
              *out++ = (unsigned char)(((*psrcdot) >> 8) << 3);
#endif
            }
            (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
        }
    }

  /* 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);

  /* And we're done! */
  return 1;
}

/*
 * SOME FINE POINTS:
 *
 * In the above loop, we ignored the return value of jpeg_write_scanlines,
 * which is the number of scanlines actually written.  We could get away
 * with this because we were only relying on the value of cinfo.next_scanline,
 * which will be incremented correctly.  If you maintain additional loop
 * variables then you should be careful to increment them properly.
 * Actually, for output to a stdio stream you needn't worry, because
 * then jpeg_write_scanlines will write all the lines passed (or else exit
 * with a fatal error).  Partial writes can only occur if you use a data
 * destination module that can demand suspension of the compressor.
 * (If you don't know what that's for, you don't need it.)
 *
 * If the compressor requires full-image buffers (for entropy-coding
 * optimization or a multi-scan JPEG file), it will create temporary
 * files for anything that doesn't fit within the maximum-memory setting.
 * (Note that temp files are NOT needed if you use the default parameters.)
 * On some systems you may need to set up a signal handler to ensure that
 * temporary files are deleted if the program is interrupted.  See libjpeg.txt.
 *
 * Scanlines MUST be supplied in top-to-bottom order if you want your JPEG
 * files to be compatible with everyone else's.  If you cannot readily read
 * your data in that order, you'll need an intermediate array to hold the
 * image.  See rdtarga.c or rdbmp.c for examples of handling bottom-to-top
 * source data using the JPEG code's internal virtual-array mechanisms.
 */



/******************** JPEG DECOMPRESSION SAMPLE INTERFACE *******************/

/* This half of the example shows how to read data from the JPEG decompressor.
 * It's a bit more refined than the above, in that we show:
 *   (a) how to modify the JPEG library's standard error-reporting behavior;
 *   (b) how to allocate workspace using the library's memory manager.
 *
 * Just to make this example a little different from the first one, we'll
 * assume that we do not intend to put the whole image into an in-memory
 * buffer, but to send it line-by-line someplace else.  We need a one-
 * scanline-high JSAMPLE array as a work buffer, and we will let the JPEG
 * memory manager allocate it for us.  This approach is actually quite useful
 * because we don't need to remember to deallocate the buffer separately: it
 * will go away automatically when the JPEG object is cleaned up.
 */


/*
 * 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:
 */

struct my_error_mgr {
  struct jpeg_error_mgr pub;	/* "public" fields */

  jmp_buf setjmp_buffer;	/* for return to caller */
};

typedef struct my_error_mgr * my_error_ptr;

/*
 * Here's the routine that will replace the standard error_exit method:
 */

METHODDEF(void)
my_error_exit (j_common_ptr cinfo)
{
  /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
  my_error_ptr myerr = (my_error_ptr) cinfo->err;

  /* Always display the message. */
  /* We could postpone this until after returning, if we chose. */
  (*cinfo->err->output_message) (cinfo);

  /* Return control to the setjmp point */
  longjmp(myerr->setjmp_buffer, 1);
}


_Bool libjpeg_decode(const uint8_t *jpeg_data, uint32_t jpeg_size, color_space_t dst_type, uint8_t *outbuffer, uint32_t *width, uint32_t *height)
{
  /* This struct contains the JPEG decompression parameters and pointers to
   * working space (which is allocated as needed by the JPEG library).
   */
  struct jpeg_decompress_struct cinfo;
  /* We use our private extension JPEG error handler.
   * Note that this struct must live as long as the main JPEG parameter
   * struct, to avoid dangling-pointer problems.
   */
  struct my_error_mgr jerr;
  /* More stuff */
  JSAMPARRAY buffer;		/* Output row buffer */
  int row_stride;		/* physical row width in output buffer */

  /* In this example we want to open the input file before doing anything else,
   * so that the setjmp() error recovery below can assume the file is open.
   * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
   * requires it in order to read binary files.
   */
  
  /* Step 1: allocate and initialize JPEG decompression object */

  /* We set up the normal JPEG error routines, then override error_exit. */
  cinfo.err = jpeg_std_error(&jerr.pub);
  jerr.pub.error_exit = my_error_exit;
  /* Establish the setjmp return context for my_error_exit to use. */
  if (setjmp(jerr.setjmp_buffer)) {
    /* If we get here, the JPEG code has signaled an error.
     * We need to clean up the JPEG object, close the input file, and return.
     */
    jpeg_destroy_decompress(&cinfo);
    return 0;
  }
  /* Now we can initialize the JPEG decompression object. */
  jpeg_create_decompress(&cinfo);
  
  /* Step 2: specify data source (eg, a file) */

  jpeg_mem_src(&cinfo, (uint8_t*)jpeg_data, jpeg_size);

  /* Step 3: read file parameters with jpeg_read_header() */

  (void) jpeg_read_header(&cinfo, TRUE);
  /* We can ignore the return value from jpeg_read_header since
   *   (a) suspension is not possible with the stdio data source, and
   *   (b) we passed TRUE to reject a tables-only JPEG file as an error.
   * See libjpeg.txt for more info.
   */

  /* Step 4: set parameters for decompression */

  /* In this example, we don't need to change any of the defaults set by
   * jpeg_read_header(), so we do nothing here.
   */
  cinfo.dct_method = JDCT_IFAST;
  cinfo.do_fancy_upsampling = 0; 
  if(COLOR_TYPE_RGB888 == dst_type){
    cinfo.out_color_space = JCS_RGB; 	/* colorspace of input image */
  } else if(COLOR_TYPE_RGB565 == dst_type){
    cinfo.out_color_space = JCS_RGB; 	/* colorspace of input image */
  } else {
    printf("Unsupported destination type\n");
    return 0;
  }
  /* Step 5: Start decompressor */

  (void) jpeg_start_decompress(&cinfo);
  /* We can ignore the return value since suspension is not possible
   * with the stdio data source.
   */

  /* We may need to do some setup of our own at this point before reading
   * the data.  After jpeg_start_decompress() we have the correct scaled
   * output image dimensions available, as well as the output colormap
   * if we asked for color quantization.
   * In this example, we need to make an output work buffer of the right size.
   */ 
  /* JSAMPLEs per row in output buffer */
  row_stride = cinfo.output_width * cinfo.output_components;
  /* Make a one-row-high sample array that will go away when done with image */
  buffer = (*cinfo.mem->alloc_sarray)
    ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
  /* Step 6: while (scan lines remain to be read) */
  /*           jpeg_read_scanlines(...); */
  if (width) {
    *width = cinfo.output_width;
  }
  if (height) {
    *height = cinfo.output_height;
  }
  
  /* Here we use the library's state variable cinfo.output_scanline as the
   * loop counter, so that we don't have to keep track ourselves.
   *///printf("w=%d, h=%d\n", cinfo.output_width, cinfo.output_height);
  while (cinfo.output_scanline < cinfo.output_height) {
    /* jpeg_read_scanlines expects an array of pointers to scanlines.
     * Here the array is only one element long, but you could ask for
     * more than one scanline at a time if that's more convenient.
     */
    if (COLOR_TYPE_RGB888 == dst_type) {
      uint8_t *row = outbuffer + 3 * (cinfo.output_scanline * cinfo.output_width);
      JSAMPARRAY out = &row;
      (void) jpeg_read_scanlines(&cinfo, out, 1);
    } else if(COLOR_TYPE_RGB565 == dst_type) {
      (void) jpeg_read_scanlines(&cinfo, buffer, 1);
      uint8_t *color=buffer[0];
      uint32_t index;
      uint32_t y = cinfo.output_scanline - 1;
      uint16_t *out = (uint16_t*)outbuffer + (y * cinfo.output_width);
      for(index = 0; index < cinfo.output_width; index++) {
        uint16_t c = ((*color) >> 3)<<11 | ((*(color+1))>> 2) << 5 | (*(color+2)) >> 3;
        out[index] = c;
        color+=3;
      }
    }
  }

  /* Step 7: Finish decompression */
  (void) jpeg_finish_decompress(&cinfo);
  /* 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).
   */

  /* And we're done! */
  return 1;
}


/*
 * SOME FINE POINTS:
 *
 * In the above code, we ignored the return value of jpeg_read_scanlines,
 * which is the number of scanlines actually read.  We could get away with
 * this because we asked for only one line at a time and we weren't using
 * a suspending data source.  See libjpeg.txt for more info.
 *
 * We cheated a bit by calling alloc_sarray() after jpeg_start_decompress();
 * we should have done it beforehand to ensure that the space would be
 * counted against the JPEG max_memory setting.  In some systems the above
 * code would risk an out-of-memory error.  However, in general we don't
 * know the output image dimensions before jpeg_start_decompress(), unless we
 * call jpeg_calc_output_dimensions().  See libjpeg.txt for more about this.
 *
 * Scanlines are returned in the same order as they appear in the JPEG file,
 * which is standardly top-to-bottom.  If you must emit data bottom-to-top,
 * you can use one of the virtual arrays provided by the JPEG memory manager
 * to invert the data.  See wrbmp.c for an example.
 *
 * As with compression, some operating modes may require temporary files.
 * On some systems you may need to set up a signal handler to ensure that
 * temporary files are deleted if the program is interrupted.  See libjpeg.txt.
 */