CImage_JPEG_streams.cpp

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/* +---------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)               |
   |                          http://www.mrpt.org/                             |
   |                                                                           |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file        |
   | See: http://www.mrpt.org/Authors - All rights reserved.                   |
   | Released under BSD License. See details in http://www.mrpt.org/License    |
   +---------------------------------------------------------------------------+ */
 
#include "base-precomp.h"  // Precompiled headers
 
#include <mrpt/utils/CImage.h>
#include <mrpt/utils/CStream.h>
 
// Universal include for all versions of OpenCV
#include <mrpt/otherlibs/do_opencv_includes.h>
 
using namespace mrpt;
using namespace mrpt::utils;
 
// ---------------------------------------------------------------------------------------
//                                                      START OF JPEG FUNCTIONS PART
// ---------------------------------------------------------------------------------------
/* Expanded data destination object for stdio output */
 
//#undef INT32
#undef FAR
#define XMD_H
 
#include <stdio.h>
 
// In Windows, we HAVE TO (YES dear...) include our custom jpeglib
//  The problem is that, without .so/.dlls, all the libs have their
//  own jpeglib and runtime checks of expected type-sizes fail
//  causing asserts.... (fix: JLBC 20/OCT/2008)
#if MRPT_HAS_JPEG_SYSTEM
        // Normal: System libraries (typ. unix)
        #include <jpeglib.h>
 
        // Convert mrpt-names to normal ones:
        #define mrpt_jpeg_source_mgr    jpeg_source_mgr
 
#elif MRPT_HAS_JPEG   // Built-in version
        #include "jpeglib/mrpt_jpeglib.h"
        #define mrpt_jpeg_source_mgr    jpeg_source_mgr
#endif
 
typedef struct
{
        struct jpeg_destination_mgr pub; /* public fields */
 
        CStream * out;          /* target stream */
        JOCTET * buffer;                /* start of buffer */
} mrpt_destination_mgr;
 
typedef mrpt_destination_mgr * mrpt_dest_ptr;
 
#define OUTPUT_BUF_SIZE  4096   /* choose an efficiently fwrite'able size */
 
/*
 * Initialize destination --- called by jpeg_start_compress
 * before any data is actually written.
 */
 
METHODDEF(void)
init_destination (j_compress_ptr cinfo)
{
mrpt_dest_ptr dest = (mrpt_dest_ptr) cinfo->dest;
 
  /* Allocate the output buffer --- it will be released when done with image */
  dest->buffer = (JOCTET *)
          (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                  OUTPUT_BUF_SIZE * sizeof(JOCTET));
 
  dest->pub.next_output_byte = dest->buffer;
  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
}
 
 
/*
 * Empty the output buffer --- called whenever buffer fills up.
 *
 * In typical applications, this should write the entire output buffer
 * (ignoring the current state of next_output_byte & free_in_buffer),
 * reset the pointer & count to the start of the buffer, and return TRUE
 * indicating that the buffer has been dumped.
 *
 * In applications that need to be able to suspend compression due to output
 * overrun, a FALSE return indicates that the buffer cannot be emptied now.
 * In this situation, the compressor will return to its caller (possibly with
 * an indication that it has not accepted all the supplied scanlines).  The
 * application should resume compression after it has made more room in the
 * output buffer.  Note that there are substantial restrictions on the use of
 * suspension --- see the documentation.
 *
 * When suspending, the compressor will back up to a convenient restart point
 * (typically the start of the current MCU). next_output_byte & free_in_buffer
 * indicate where the restart point will be if the current call returns FALSE.
 * Data beyond this point will be regenerated after resumption, so do not
 * write it out when emptying the buffer externally.
 */
 
METHODDEF(boolean)
empty_output_buffer (j_compress_ptr cinfo)
{
  mrpt_dest_ptr dest = (mrpt_dest_ptr) cinfo->dest;
 
  dest->out->WriteBuffer( dest->buffer, OUTPUT_BUF_SIZE);
 
  dest->pub.next_output_byte = dest->buffer;
  dest->pub.free_in_buffer = OUTPUT_BUF_SIZE;
 
  return TRUE;
}
 
 
/*
 * Terminate destination --- called by jpeg_finish_compress
 * after all data has been written.  Usually needs to flush buffer.
 *
 * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
 * application must deal with any cleanup that should happen even
 * for error exit.
 */
 
METHODDEF(void)
term_destination (j_compress_ptr cinfo)
{
  mrpt_dest_ptr dest = (mrpt_dest_ptr) cinfo->dest;
  size_t datacount = OUTPUT_BUF_SIZE - dest->pub.free_in_buffer;
 
  /* Write any data remaining in the buffer */
  if (datacount > 0)
        dest->out->WriteBuffer( dest->buffer, (int)datacount);
 
}
 
GLOBAL(void)
jpeg_stdio_dest (j_compress_ptr cinfo, CStream * out)
{
  mrpt_dest_ptr dest;
 
  /* The destination object is made permanent so that multiple JPEG images
   * can be written to the same file without re-executing jpeg_stdio_dest.
   * This makes it dangerous to use this manager and a different destination
   * manager serially with the same JPEG object, because their private object
   * sizes may be different.  Caveat programmer.
   */
  if (cinfo->dest == NULL) {    /* first time for this JPEG object? */
        cinfo->dest = (jpeg_destination_mgr *)
                (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
                                  sizeof(mrpt_destination_mgr));
  }
 
  dest = (mrpt_dest_ptr) cinfo->dest;
  dest->pub.init_destination = init_destination;
  dest->pub.empty_output_buffer = empty_output_buffer;
  dest->pub.term_destination = term_destination;
  dest->out = out;
}
 
// -------------------------------------------------------------
 
/* Expanded data source object for stdio input */
 
typedef struct
{
  mrpt_jpeg_source_mgr pub;     /* public fields */
  CStream * in;         /* source stream */
  JOCTET * buffer;              /* start of buffer */
  boolean start_of_file;        /* have we gotten any data yet? */
} my_source_mgr;
 
typedef my_source_mgr * my_src_ptr;
 
#define INPUT_BUF_SIZE  4096    /* choose an efficiently fread'able size */
 
/*
 * Initialize source --- called by jpeg_read_header
 * before any data is actually read.
 */
 
METHODDEF(void)
init_source (j_decompress_ptr cinfo)
{
  my_src_ptr src = (my_src_ptr) cinfo->src;
 
  /* We reset the empty-input-file flag for each image,
   * but we don't clear the input buffer.
   * This is correct behavior for reading a series of images from one source.
   */
  src->start_of_file = TRUE;
}
 
 
/*
 * Fill the input buffer --- called whenever buffer is emptied.
 *
 * In typical applications, this should read fresh data into the buffer
 * (ignoring the current state of next_input_byte & bytes_in_buffer),
 * reset the pointer & count to the start of the buffer, and return TRUE
 * indicating that the buffer has been reloaded.  It is not necessary to
 * fill the buffer entirely, only to obtain at least one more byte.
 *
 * There is no such thing as an EOF return.  If the end of the file has been
 * reached, the routine has a choice of ERREXIT() or inserting fake data into
 * the buffer.  In most cases, generating a warning message and inserting a
 * fake EOI marker is the best course of action --- this will allow the
 * decompressor to output however much of the image is there.  However,
 * the resulting error message is misleading if the real problem is an empty
 * input file, so we handle that case specially.
 *
 * In applications that need to be able to suspend compression due to input
 * not being available yet, a FALSE return indicates that no more data can be
 * obtained right now, but more may be forthcoming later.  In this situation,
 * the decompressor will return to its caller (with an indication of the
 * number of scanlines it has read, if any).  The application should resume
 * decompression after it has loaded more data into the input buffer.  Note
 * that there are substantial restrictions on the use of suspension --- see
 * the documentation.
 *
 * When suspending, the decompressor will back up to a convenient restart point
 * (typically the start of the current MCU). next_input_byte & bytes_in_buffer
 * indicate where the restart point will be if the current call returns FALSE.
 * Data beyond this point must be rescanned after resumption, so move it to
 * the front of the buffer rather than discarding it.
 */
 
METHODDEF(boolean)
fill_input_buffer (j_decompress_ptr cinfo)
{
  my_src_ptr src = (my_src_ptr) cinfo->src;
  size_t nbytes;
 
  nbytes = src->in->ReadBuffer( src->buffer, INPUT_BUF_SIZE);
 
  if (nbytes <= 0)
  {
        if (src->start_of_file) /* Treat empty input file as fatal error */
        {
                THROW_EXCEPTION("Error looking for JPEG start data!")
        }
 
        /* Insert a fake EOI marker */
        src->buffer[0] = (JOCTET) 0xFF;
        src->buffer[1] = (JOCTET) JPEG_EOI;
        nbytes = 2;
  }
 
  src->pub.next_input_byte = src->buffer;
  src->pub.bytes_in_buffer = nbytes;
  src->start_of_file = FALSE;
 
  return TRUE;
}
 
 
/*
 * Skip data --- used to skip over a potentially large amount of
 * uninteresting data (such as an APPn marker).
 *
 * Writers of suspendable-input applications must note that skip_input_data
 * is not granted the right to give a suspension return.  If the skip extends
 * beyond the data currently in the buffer, the buffer can be marked empty so
 * that the next read will cause a fill_input_buffer call that can suspend.
 * Arranging for additional bytes to be discarded before reloading the input
 * buffer is the application writer's problem.
 */
 
METHODDEF(void)
skip_input_data (j_decompress_ptr cinfo, long num_bytes)
{
  my_src_ptr src = (my_src_ptr) cinfo->src;
 
  /* Just a dumb implementation for now.  Could use fseek() except
   * it doesn't work on pipes.  Not clear that being smart is worth
   * any trouble anyway --- large skips are infrequent.
   */
  if (num_bytes > 0) {
        while (num_bytes > (long) src->pub.bytes_in_buffer) {
          num_bytes -= (long) src->pub.bytes_in_buffer;
          (void) fill_input_buffer(cinfo);
          /* note we assume that fill_input_buffer will never return FALSE,
           * so suspension need not be handled.
           */
        }
        src->pub.next_input_byte += (size_t) num_bytes;
        src->pub.bytes_in_buffer -= (size_t) num_bytes;
  }
}
 
 
/*
 * An additional method that can be provided by data source modules is the
 * resync_to_restart method for error recovery in the presence of RST markers.
 * For the moment, this source module just uses the default resync method
 * provided by the JPEG library.  That method assumes that no backtracking
 * is possible.
 */
 
 
/*
 * Terminate source --- called by jpeg_finish_decompress
 * after all data has been read.  Often a no-op.
 *
 * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
 * application must deal with any cleanup that should happen even
 * for error exit.
 */
 
METHODDEF(void)
term_source (j_decompress_ptr cinfo)
{
        MRPT_UNUSED_PARAM(cinfo);
  /* no work necessary here */
}
 
 
/*
 * Prepare for input from a stdio stream.
 * The caller must have already opened the stream, and is responsible
 * for closing it after finishing decompression.
 */
 
GLOBAL(void)
jpeg_stdio_src (j_decompress_ptr cinfo, CStream * in)
{
  my_src_ptr src;
 
  /* The source object and input buffer are made permanent so that a series
   * of JPEG images can be read from the same file by calling jpeg_stdio_src
   * only before the first one.  (If we discarded the buffer at the end of
   * one image, we'd likely lose the start of the next one.)
   * This makes it unsafe to use this manager and a different source
   * manager serially with the same JPEG object.  Caveat programmer.
   */
  if (cinfo->src == NULL)
  {     /* first time for this JPEG object? */
        cinfo->src = (mrpt_jpeg_source_mgr *)
                (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
                                  sizeof(my_source_mgr));
        src = (my_src_ptr) cinfo->src;
        src->buffer = (JOCTET *)
          (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
                                  INPUT_BUF_SIZE * sizeof(JOCTET));
  }
 
  src = (my_src_ptr) cinfo->src;
  src->pub.init_source = init_source;
  src->pub.fill_input_buffer = fill_input_buffer;
  src->pub.skip_input_data = skip_input_data;
  src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
  src->pub.term_source = term_source;
  src->in = in;
  src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
  src->pub.next_input_byte = NULL; /* until buffer loaded */
}
 
// ---------------------------------------------------------------------------------------
//                                                      END OF JPEG FUNCTIONS PART
// ---------------------------------------------------------------------------------------
 
 
 
/*---------------------------------------------------------------
                                        saveToStreamAsJPEG
 ---------------------------------------------------------------*/
void  CImage::saveToStreamAsJPEG( CStream &out, const int jpeg_quality ) const
{
#if MRPT_HAS_OPENCV
        MRPT_START
 
        makeSureImageIsLoaded();   // For delayed loaded images stored externally
 
        struct jpeg_compress_struct             cinfo;
        struct jpeg_error_mgr                   jerr;
 
        const IplImage *ipl = static_cast<const IplImage*>(img);
 
        const unsigned int nCols = ipl->width;
        const unsigned int nRows = ipl->height;
        const bool is_color = (ipl->nChannels==3);
 
 
        // Some previous verification:
        ASSERT_(nCols>=1 && nRows>=1)
        ASSERT_(ipl)
        ASSERT_(ipl->nChannels == 1 || ipl->nChannels == 3)
 
        // 1) Initialization of the JPEG compresion object:
        // --------------------------------------------------
        cinfo.err =  jpeg_std_error(&jerr);
         jpeg_create_compress(&cinfo);
 
        // 2) Set the destination of jpeg data:
        // --------------------------------------------------
        jpeg_stdio_dest( &cinfo, &out );
 
        // 3) Set parameters for compression:
        // --------------------------------------------------
        cinfo.image_width = nCols;
        cinfo.image_height = nRows;
        cinfo.input_components = is_color ? 3:1;
        cinfo.in_color_space = is_color ? JCS_RGB : JCS_GRAYSCALE;
 
        jpeg_set_defaults(&cinfo);
        /* Make optional parameter settings here */
        /* 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 /* quality per cent */, TRUE /* limit to baseline-JPEG values */);
 
        // 4) Start:
        // --------------------------------------------------
        jpeg_start_compress(&cinfo, TRUE);
 
        // 5) Write scan lines:
        // --------------------------------------------------
        if (is_color)
        {
                JSAMPROW row_pointer[1];                /* pointer to a single row */
                row_pointer[0] = (JSAMPROW)new char[ ipl->widthStep ];
 
                for (unsigned int row = 0; row<nRows;row++)
                {
                        // Flip RGB bytes order!
                        char *src;
                        if (ipl->origin == 0)
                                        src = &ipl->imageData[ row * ipl->widthStep ];
                        else    src = &ipl->imageData[ (nRows-1-row) * ipl->widthStep ];
                        char *target = (char *)row_pointer[0];
                        for (unsigned int col=0;col<nCols;col++)
                        {
                                target[0] = src[2];
                                target[1] = src[1];
                                target[2] = src[0];
 
                                target+=3;
                                src+=3;
                        }
 
                        if (1!=  jpeg_write_scanlines(&cinfo, row_pointer, 1))
                        {
                                THROW_EXCEPTION("jpeg_write_scanlines: didn't work!!");
                        }
                }
 
                delete[] row_pointer[0];
        } // end "color"
        else
        {       // Is grayscale:
                JSAMPROW                                                row_pointer[1];         /* pointer to a single row */
 
                for (unsigned int row = 0; row<nRows;row++)
                {
                        if (ipl->origin == 0)
                                        row_pointer[0] = (JSAMPROW) &ipl->imageData[ row * ipl->widthStep ];
                        else    row_pointer[0] = (JSAMPROW) &ipl->imageData[ (nRows-1-row) * ipl->widthStep ];
 
                        // Gray scale:
                        if (1!=  jpeg_write_scanlines(&cinfo, row_pointer, 1))
                        {
                                THROW_EXCEPTION("jpeg_write_scanlines: didn't work!!");
                        }
                }
        }
 
        // 6) Compress and finish:
        // --------------------------------------------------
        jpeg_finish_compress(&cinfo);
        jpeg_destroy_compress(&cinfo);
 
        // DONE!
        MRPT_END
#endif
}
 
 
/*---------------------------------------------------------------
                                        saveToStreamAsJPEG
 ---------------------------------------------------------------*/
void  CImage::loadFromStreamAsJPEG( CStream &in )
{
#if MRPT_HAS_OPENCV
        MRPT_START
 
        struct jpeg_decompress_struct cinfo;
        struct jpeg_error_mgr         jerr;
 
        /* 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);
 
        /* Now we can initialize the JPEG decompression object. */
        jpeg_create_decompress(&cinfo);
 
        /* Step 2: specify data source (eg, a file) */
        jpeg_stdio_src(&cinfo, &in);
 
        /* Step 3: read file parameters with jpeg_read_header() */
        jpeg_read_header(&cinfo, TRUE);
 
        /* Step 4: set parameters for decompression */
 
        /* Step 5: Start decompressor */
        jpeg_start_decompress(&cinfo);
 
        /* 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 */
        /* physical row width in output buffer */
        const int row_stride = cinfo.output_width * cinfo.output_components;
        /* Make a one-row-high sample array that will go away when done with image */
        /* Output row buffer */
        JSAMPARRAY buffer = (*cinfo.mem->alloc_sarray)
                ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
 
 
        // Resize the CImage now:
        this->changeSize( cinfo.output_width, cinfo.output_height, cinfo.out_color_components, true );
        IplImage *ipl = static_cast<IplImage*>(img);
 
        /* Step 6: while (scan lines remain to be read) */
        /*           jpeg_read_scanlines(...); */
 
        /* 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.
        */
        const unsigned int nCols = cinfo.output_width;
        const unsigned int nRows = cinfo.output_height;
 
        for (unsigned int row = 0; row<nRows;row++)
        {
                /* 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.
                */
                jpeg_read_scanlines(&cinfo, buffer, 1);
 
                /* Copy into the CImage object */
                if (isColor())
                {
                        // Flip RGB bytes order!
                        char *target = &ipl->imageData[ row * ipl->widthStep ];
                        const char *src = (char *)buffer[0];
                        for (unsigned int col=0;col<nCols;col++)
                        {
                                target[0] = src[2];
                                target[1] = src[1];
                                target[2] = src[0];
 
                                target+=3;
                                src+=3;
                        }
                }
                else
                {
                        // Gray scale:
                        memcpy( &ipl->imageData[ row * ipl->widthStep ],
                                        buffer[0],
                                        row_stride );
                }
 
        }
 
        /* Step 7: Finish decompression */
 
        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);
 
        // DONE!
        MRPT_END
#endif
}