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|
/**
* @file llimagejpeg.cpp
*
* $LicenseInfo:firstyear=2002&license=viewerlgpl$
* Second Life Viewer Source Code
* Copyright (C) 2010, Linden Research, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License only.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
* $/LicenseInfo$
*/
#include "linden_common.h"
#include "stdtypes.h"
#include "llimagejpeg.h"
#include "llerror.h"
#include "llexception.h"
jmp_buf LLImageJPEG::sSetjmpBuffer ;
LLImageJPEG::LLImageJPEG(S32 quality)
: LLImageFormatted(IMG_CODEC_JPEG),
mOutputBuffer( NULL ),
mOutputBufferSize( 0 ),
mEncodeQuality( quality ) // 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/catch will crash on Mac and Linux if LLImageJPEG::errorExit throws an error
//so as instead, we use setjmp/longjmp to avoid this crash, which is the best we can get. --bao
//
#if !(LL_DARWIN && defined(__arm64__))
if(setjmp(sSetjmpBuffer))
{
jpeg_destroy_decompress(&cinfo);
return false;
}
#endif
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
}
// Returns true when done, whether or not decode was successful.
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 true; // done
}
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/catch will crash on Mac and Linux if LLImageJPEG::errorExit throws an error
//so as instead, we use setjmp/longjmp to avoid this crash, which is the best we can get. --bao
//
#if !(LL_DARWIN && defined(__arm64__))
if(setjmp(sSetjmpBuffer))
{
jpeg_destroy_decompress(&cinfo);
return true; // done
}
#endif
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)
if (!raw_image->resize(getWidth(), getHeight(), getComponents()))
{
throw std::bad_alloc();
}
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 (std::bad_alloc&)
{
setLastError( "Out of memory");
jpeg_destroy_decompress(&cinfo);
return true; // done
}
catch (int)
{
jpeg_destroy_decompress(&cinfo);
return true; // done
}
// 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 true; // done
}
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(std::nothrow) U8[ new_buffer_size ];
if (!new_buffer)
{
self->setLastError("Out of memory in LLImageJPEG::encodeEmptyOutputBuffer( j_compress_ptr cinfo )");
LLTHROW(LLContinueError("Out of memory in LLImageJPEG::encodeEmptyOutputBuffer( j_compress_ptr cinfo )"));
}
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
#if !(LL_DARWIN && defined(__arm64__))
longjmp(sSetjmpBuffer, 1) ;
#endif
}
// 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);
std::string error = buffer ;
LLImage::setLastError(error);
bool is_decode = (cinfo->is_decompressor != 0);
LL_WARNS() << "LLImageJPEG " << (is_decode ? "decode " : "encode ") << " failed: " << buffer << LL_ENDL;
}
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(std::nothrow) U8[ mOutputBufferSize ];
if (mOutputBuffer == NULL)
{
mOutputBufferSize = 0;
setLastError("Failed to allocate output buffer");
return false;
}
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
//
//try/catch will crash on Mac and Linux if LLImageJPEG::errorExit throws an error
//so as instead, we use setjmp/longjmp to avoid this crash, which is the best we can get. --bao
//
#if !(LL_DARWIN && defined(__arm64__))
if( setjmp(sSetjmpBuffer) )
{
// 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;
}
#endif
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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