llimagejpeg.cpp

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#include "linden_common.h"
#include "stdtypes.h"

#include "llimagejpeg.h"

#include "llerror.h"

LLImageJPEG::LLImageJPEG() 
        :
        LLImageFormatted(IMG_CODEC_JPEG),
        mOutputBuffer( NULL ),
        mOutputBufferSize( 0 ),
        mEncodeQuality( 75 )            // on a scale from 1 to 100
{
}

LLImageJPEG::~LLImageJPEG()
{
        llassert( !mOutputBuffer ); // Should already be deleted at end of encode.
        delete[] mOutputBuffer;
}

BOOL LLImageJPEG::updateData()
{
        resetLastError();

        // Check to make sure that this instance has been initialized with data
        if (!getData() || (0 == getDataSize()))
        {
                setLastError("Uninitialized instance of LLImageJPEG");
                return FALSE;
        }

        // Step 1: allocate and initialize JPEG decompression object

        // 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;
        cinfo.client_data = this;

        struct jpeg_error_mgr jerr;
        cinfo.err = jpeg_std_error(&jerr);
        
        // Customize with our own callbacks
        jerr.error_exit =               &LLImageJPEG::errorExit;                        // Error exit handler: does not return to caller
        jerr.emit_message =             &LLImageJPEG::errorEmitMessage;         // Conditionally emit a trace or warning message
        jerr.output_message =   &LLImageJPEG::errorOutputMessage;       // Routine that actually outputs a trace or error message

        try
        {
                // Now we can initialize the JPEG decompression object.
                jpeg_create_decompress(&cinfo);

                // Step 2: specify data source
                // (Code is modified version of jpeg_stdio_src();
                if (cinfo.src == NULL)
                {       
                        cinfo.src = (struct jpeg_source_mgr *)
                                (*cinfo.mem->alloc_small) ((j_common_ptr) &cinfo, JPOOL_PERMANENT,
                                sizeof(struct jpeg_source_mgr));
                }
                cinfo.src->init_source  =               &LLImageJPEG::decodeInitSource;
                cinfo.src->fill_input_buffer =  &LLImageJPEG::decodeFillInputBuffer;
                cinfo.src->skip_input_data =    &LLImageJPEG::decodeSkipInputData;
                cinfo.src->resync_to_restart = jpeg_resync_to_restart; // For now, use default method, but we should be able to do better.
                cinfo.src->term_source =                &LLImageJPEG::decodeTermSource;

                cinfo.src->bytes_in_buffer =    getDataSize();
                cinfo.src->next_input_byte =    getData();
                
                // Step 3: read file parameters with jpeg_read_header()
                jpeg_read_header( &cinfo, TRUE );

                // Data set by jpeg_read_header
                setSize(cinfo.image_width, cinfo.image_height, 3); // Force to 3 components (RGB)

                /*
                // More data set by jpeg_read_header
                cinfo.num_components;
                cinfo.jpeg_color_space; // Colorspace of image
                cinfo.saw_JFIF_marker;          // TRUE if a JFIF APP0 marker was seen
                cinfo.JFIF_major_version;       // Version information from JFIF marker
                cinfo.JFIF_minor_version;  //
                cinfo.density_unit;             // Resolution data from JFIF marker
                cinfo.X_density;
                cinfo.Y_density;
                cinfo.saw_Adobe_marker; // TRUE if an Adobe APP14 marker was seen
                cinfo.Adobe_transform;     // Color transform code from Adobe marker
                */
        }
        catch (int)
        {
                jpeg_destroy_decompress(&cinfo);

                return FALSE;
        }
        // Step 4: Release JPEG decompression object 
        jpeg_destroy_decompress(&cinfo);

        return TRUE;
}

// Initialize source --- called by jpeg_read_header
// before any data is actually read.
void LLImageJPEG::decodeInitSource( j_decompress_ptr cinfo )
{
        // no work necessary here
}

// Fill the input buffer --- called whenever buffer is emptied.
boolean LLImageJPEG::decodeFillInputBuffer( j_decompress_ptr cinfo )
{
//      jpeg_source_mgr* src = cinfo->src;
//      LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;

        // Should never get here, since we provide the entire buffer up front.
        ERREXIT(cinfo, JERR_INPUT_EMPTY);

        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.
void LLImageJPEG::decodeSkipInputData (j_decompress_ptr cinfo, long num_bytes)
{
        jpeg_source_mgr* src = cinfo->src;
//      LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;

    src->next_input_byte += (size_t) num_bytes;
    src->bytes_in_buffer -= (size_t) num_bytes;
}

void LLImageJPEG::decodeTermSource (j_decompress_ptr cinfo)
{
  // no work necessary here
}


BOOL LLImageJPEG::decode(LLImageRaw* raw_image, F32 decode_time)
{
        llassert_always(raw_image);
        
        resetLastError();
        
        // Check to make sure that this instance has been initialized with data
        if (!getData() || (0 == getDataSize()))
        {
                setLastError("LLImageJPEG trying to decode an image with no data!");
                return FALSE;
        }
        
        S32 row_stride = 0;
        U8* raw_image_data = NULL;

        // Step 1: allocate and initialize JPEG decompression object

        // 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;

        struct jpeg_error_mgr jerr;
        cinfo.err = jpeg_std_error(&jerr);
        
        // Customize with our own callbacks
        jerr.error_exit =               &LLImageJPEG::errorExit;                        // Error exit handler: does not return to caller
        jerr.emit_message =             &LLImageJPEG::errorEmitMessage;         // Conditionally emit a trace or warning message
        jerr.output_message =   &LLImageJPEG::errorOutputMessage;       // Routine that actually outputs a trace or error message
        

        try
        {
                // Now we can initialize the JPEG decompression object.
                jpeg_create_decompress(&cinfo);

                // Step 2: specify data source
                // (Code is modified version of jpeg_stdio_src();
                if (cinfo.src == NULL)
                {       
                        cinfo.src = (struct jpeg_source_mgr *)
                                (*cinfo.mem->alloc_small) ((j_common_ptr) &cinfo, JPOOL_PERMANENT,
                                sizeof(struct jpeg_source_mgr));
                }
                cinfo.src->init_source  =               &LLImageJPEG::decodeInitSource;
                cinfo.src->fill_input_buffer =  &LLImageJPEG::decodeFillInputBuffer;
                cinfo.src->skip_input_data =    &LLImageJPEG::decodeSkipInputData;
                cinfo.src->resync_to_restart = jpeg_resync_to_restart; // For now, use default method, but we should be able to do better.
                cinfo.src->term_source =                &LLImageJPEG::decodeTermSource;
                cinfo.src->bytes_in_buffer =    getDataSize();
                cinfo.src->next_input_byte =    getData();
                
                // Step 3: read file parameters with jpeg_read_header()
                
                jpeg_read_header(&cinfo, TRUE);

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

                setSize(cinfo.image_width, cinfo.image_height, 3); // Force to 3 components (RGB)

                raw_image->resize(getWidth(), getHeight(), getComponents());
                raw_image_data = raw_image->getData();
                
                
                // Step 4: set parameters for decompression 
                cinfo.out_color_components = 3;
                cinfo.out_color_space = JCS_RGB;
   

                // Step 5: Start decompressor 
                
                jpeg_start_decompress(&cinfo);
                // We can ignore the return value since suspension is not possible
                // with our 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;
                
                // 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.
                
                // Move pointer to last line
                raw_image_data += row_stride * (cinfo.output_height - 1);

                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.
                        
                        jpeg_read_scanlines(&cinfo, &raw_image_data, 1);
                        raw_image_data -= row_stride;  // move pointer up a line
                }

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

                // Step 8: Release JPEG decompression object 
                jpeg_destroy_decompress(&cinfo);
        }

        catch (int)
        {
                jpeg_destroy_decompress(&cinfo);
                return FALSE;
        }

        // Check to see whether any corrupt-data warnings occurred
        if( jerr.num_warnings != 0 )
        {
                // TODO: extract the warning to find out what went wrong.
                setLastError( "Unable to decode JPEG image.");
                return FALSE;
        }

        return TRUE;
}


// Initialize destination --- called by jpeg_start_compress before any data is actually written.
// static
void LLImageJPEG::encodeInitDestination ( j_compress_ptr cinfo )
{
  LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;

  cinfo->dest->next_output_byte = self->mOutputBuffer;
  cinfo->dest->free_in_buffer = self->mOutputBufferSize;
}


//  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.

boolean LLImageJPEG::encodeEmptyOutputBuffer( j_compress_ptr cinfo )
{
  LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;

  // Should very rarely happen, since our output buffer is
  // as large as the input to start out with.
  
  // Double the buffer size;
  S32 new_buffer_size = self->mOutputBufferSize * 2;
  U8* new_buffer = new U8[ new_buffer_size ];
  if (!new_buffer)
  {
        llerrs << "Out of memory in LLImageJPEG::encodeEmptyOutputBuffer( j_compress_ptr cinfo )" << llendl;
        return FALSE;
  }
  memcpy( new_buffer, self->mOutputBuffer, self->mOutputBufferSize );   /* Flawfinder: ignore */
  delete[] self->mOutputBuffer;
  self->mOutputBuffer = new_buffer;

  cinfo->dest->next_output_byte = self->mOutputBuffer + self->mOutputBufferSize;
  cinfo->dest->free_in_buffer = self->mOutputBufferSize;
  self->mOutputBufferSize = new_buffer_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.
void LLImageJPEG::encodeTermDestination( j_compress_ptr cinfo )
{
        LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;

        S32 file_bytes = (S32)(self->mOutputBufferSize - cinfo->dest->free_in_buffer);
        self->allocateData(file_bytes);

        memcpy( self->getData(), self->mOutputBuffer, file_bytes );     /* Flawfinder: ignore */
}

// static 
void LLImageJPEG::errorExit( j_common_ptr cinfo )       
{
        //LLImageJPEG* self = (LLImageJPEG*) cinfo->client_data;

        // Always display the message
        (*cinfo->err->output_message)(cinfo);

        // Let the memory manager delete any temp files
        jpeg_destroy(cinfo);

        // Return control to the setjmp point
        throw 1;
}

// Decide whether to emit a trace or warning message.
// msg_level is one of:
//   -1: recoverable corrupt-data warning, may want to abort.
//    0: important advisory messages (always display to user).
//    1: first level of tracing detail.
//    2,3,...: successively more detailed tracing messages.
// An application might override this method if it wanted to abort on warnings
// or change the policy about which messages to display.
// static 
void LLImageJPEG::errorEmitMessage( j_common_ptr cinfo, int msg_level )
{
  struct jpeg_error_mgr * err = cinfo->err;

  if (msg_level < 0) 
  {
          // It's a warning message.  Since corrupt files may generate many warnings,
          // the policy implemented here is to show only the first warning,
          // unless trace_level >= 3.
          if (err->num_warnings == 0 || err->trace_level >= 3)
          {
                  (*err->output_message) (cinfo);
          }
          // Always count warnings in num_warnings.
          err->num_warnings++;
  }
  else 
  {
          // It's a trace message.  Show it if trace_level >= msg_level.
          if (err->trace_level >= msg_level)
          {
                  (*err->output_message) (cinfo);
          }
  }
}

// static 
void LLImageJPEG::errorOutputMessage( j_common_ptr cinfo )
{
        // Create the message
        char buffer[JMSG_LENGTH_MAX];   /* Flawfinder: ignore */
        (*cinfo->err->format_message) (cinfo, buffer);

        ((LLImageJPEG*) cinfo->client_data)->setLastError( buffer );

        BOOL is_decode = (cinfo->is_decompressor != 0);
        llwarns << "LLImageJPEG " << (is_decode ? "decode " : "encode ") << " failed: " << buffer << llendl;
}

BOOL LLImageJPEG::encode( const LLImageRaw* raw_image, F32 encode_time )
{
        llassert_always(raw_image);
        
        resetLastError();

        switch( raw_image->getComponents() )
        {
        case 1:
        case 3:
                break;
        default:
                setLastError("Unable to encode a JPEG image that doesn't have 1 or 3 components.");
                return FALSE;
        }

        setSize(raw_image->getWidth(), raw_image->getHeight(), raw_image->getComponents());

        // Allocate a temporary buffer big enough to hold the entire compressed image (and then some)
        // (Note: we make it bigger in emptyOutputBuffer() if we need to)
        delete[] mOutputBuffer;
        mOutputBufferSize = getWidth() * getHeight() * getComponents() + 1024;
        mOutputBuffer = new U8[ mOutputBufferSize ];

        const U8* raw_image_data = NULL;
        S32 row_stride = 0;

        // Step 1: allocate and initialize JPEG compression object

        // This struct contains the JPEG compression parameters and pointers to
        // working space (which is allocated as needed by the JPEG library).
        struct jpeg_compress_struct cinfo;
        cinfo.client_data = this;

        // 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.
        struct jpeg_error_mgr jerr;
        cinfo.err = jpeg_std_error(&jerr);

        // Customize with our own callbacks
        jerr.error_exit =               &LLImageJPEG::errorExit;                        // Error exit handler: does not return to caller
        jerr.emit_message =             &LLImageJPEG::errorEmitMessage;         // Conditionally emit a trace or warning message
        jerr.output_message =   &LLImageJPEG::errorOutputMessage;       // Routine that actually outputs a trace or error message

        // Establish the setjmp return context mSetjmpBuffer.  Used by library to abort.
        if( setjmp(mSetjmpBuffer) ) 
        {
                // 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_compress(&cinfo);
                delete[] mOutputBuffer;
                mOutputBuffer = NULL;
                mOutputBufferSize = 0;
                return FALSE;
        }

        try
        {

                // Now we can initialize the JPEG compression object.
                jpeg_create_compress(&cinfo);

                // Step 2: specify data destination
                // (code is a modified form of jpeg_stdio_dest() )
                if( cinfo.dest == NULL)
                {       
                        cinfo.dest = (struct jpeg_destination_mgr *)
                                (*cinfo.mem->alloc_small) ((j_common_ptr) &cinfo, JPOOL_PERMANENT,
                                sizeof(struct jpeg_destination_mgr));
                }
                cinfo.dest->next_output_byte =          mOutputBuffer;          // => next byte to write in buffer
                cinfo.dest->free_in_buffer =            mOutputBufferSize;      // # of byte spaces remaining in buffer
                cinfo.dest->init_destination =          &LLImageJPEG::encodeInitDestination;
                cinfo.dest->empty_output_buffer =       &LLImageJPEG::encodeEmptyOutputBuffer;
                cinfo.dest->term_destination =          &LLImageJPEG::encodeTermDestination;

                // 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 = getWidth();         // image width and height, in pixels 
                cinfo.image_height = getHeight();

                switch( getComponents() )
                {
                case 1:
                        cinfo.input_components = 1;             // # of color components per pixel
                        cinfo.in_color_space = JCS_GRAYSCALE; // colorspace of input image
                        break;
                case 3:
                        cinfo.input_components = 3;             // # of color components per pixel
                        cinfo.in_color_space = JCS_RGB; // colorspace of input image
                        break;
                default:
                        setLastError("Unable to encode a JPEG image that doesn't have 1 or 3 components.");
                        return FALSE;
                }

                // 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.
                jpeg_set_quality(&cinfo, mEncodeQuality, 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 = getWidth() * getComponents();      // JSAMPLEs per row in image_buffer

                // NOTE: For compatibility with LLImage, we need to invert the rows.
                raw_image_data = raw_image->getData();
                
                const U8* last_row_data = raw_image_data + (getHeight()-1) * row_stride;

                JSAMPROW row_pointer[1];                                // pointer to JSAMPLE row[s]
                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.

                        //Ugly const uncast here (jpeg_write_scanlines should take a const* but doesn't)
                        //row_pointer[0] = (JSAMPROW)(raw_image_data + (cinfo.next_scanline * row_stride));
                        row_pointer[0] = (JSAMPROW)(last_row_data - (cinfo.next_scanline * row_stride));

                        jpeg_write_scanlines(&cinfo, row_pointer, 1);
                }

                //   Step 6: Finish compression 
                jpeg_finish_compress(&cinfo);

                // After finish_compress, we can release the temp output buffer. 
                delete[] mOutputBuffer;
                mOutputBuffer = NULL;
                mOutputBufferSize = 0;

                //   Step 7: release JPEG compression object 
                jpeg_destroy_compress(&cinfo);
        }

        catch(int)
        {
                jpeg_destroy_compress(&cinfo);
                delete[] mOutputBuffer;
                mOutputBuffer = NULL;
                mOutputBufferSize = 0;
                return FALSE;
        }

        return TRUE;
}

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