mxwcore-legion/dep/g3dlite/source/GImage_jpeg.cpp

447 lines
11 KiB
C++

/**
@file GImage_jpeg.cpp
@author Morgan McGuire, http://graphics.cs.williams.edu
@created 2002-05-27
@edited 2009-04-20
*/
#include "G3D/platform.h"
#include "G3D/GImage.h"
#include "G3D/BinaryInput.h"
#include "G3D/BinaryOutput.h"
#include <cstring>
extern "C" {
#ifdef G3D_LINUX
# include <jconfig.h>
# include <jpeglib.h>
#else
# include "jconfig.h"
# include "jpeglib.h"
#endif
}
namespace G3D {
const int jpegQuality = 96;
/**
The IJG library needs special setup for compress/decompressing
from memory. These classes provide them.
The format of this class is defined by the IJG library; do not
change it.
*/
class memory_destination_mgr {
public:
struct jpeg_destination_mgr pub;
JOCTET* buffer;
int size;
int count;
};
typedef memory_destination_mgr* mem_dest_ptr;
/**
Signature dictated by IJG.
*/
static void init_destination (
j_compress_ptr cinfo) {
mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;
dest->pub.next_output_byte = dest->buffer;
dest->pub.free_in_buffer = dest->size;
dest->count=0;
}
/**
Signature dictated by IJG.
*/
static boolean empty_output_buffer (
j_compress_ptr cinfo) {
mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;
dest->pub.next_output_byte = dest->buffer;
dest->pub.free_in_buffer = dest->size;
return TRUE;
}
/**
Signature dictated by IJG.
*/
static void term_destination (
j_compress_ptr cinfo) {
mem_dest_ptr dest = (mem_dest_ptr) cinfo->dest;
dest->count = dest->size - dest->pub.free_in_buffer;
}
/**
Signature dictated by IJG.
*/
static void jpeg_memory_dest (
j_compress_ptr cinfo,
JOCTET* buffer,
int size) {
mem_dest_ptr dest;
if (cinfo->dest == NULL) {
// First time for this JPEG object; call the
// IJG allocator to get space.
cinfo->dest = (struct jpeg_destination_mgr*)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo,
JPOOL_PERMANENT,
sizeof(memory_destination_mgr));
}
dest = (mem_dest_ptr) cinfo->dest;
dest->size = size;
dest->buffer = buffer;
dest->pub.init_destination = init_destination;
dest->pub.empty_output_buffer = empty_output_buffer;
dest->pub.term_destination = term_destination;
}
////////////////////////////////////////////////////////////////////////////////////////
#define INPUT_BUF_SIZE 4096
/**
Structure dictated by IJG.
*/
class memory_source_mgr {
public:
struct jpeg_source_mgr pub;
int source_size;
unsigned char* source_data;
boolean start_of_data;
JOCTET* buffer;
};
typedef memory_source_mgr* mem_src_ptr;
/**
Signature dictated by IJG.
*/
static void init_source(
j_decompress_ptr cinfo) {
mem_src_ptr src = (mem_src_ptr) cinfo->src;
src->start_of_data = TRUE;
}
/**
Signature dictated by IJG.
*/
static boolean fill_input_buffer(
j_decompress_ptr cinfo) {
mem_src_ptr src = (mem_src_ptr) cinfo->src;
size_t bytes_read = 0;
if (src->source_size > INPUT_BUF_SIZE)
bytes_read = INPUT_BUF_SIZE;
else
bytes_read = src->source_size;
memcpy (src->buffer, src->source_data, bytes_read);
src->source_data += bytes_read;
src->source_size -= bytes_read;
src->pub.next_input_byte = src->buffer;
src->pub.bytes_in_buffer = bytes_read;
src->start_of_data = FALSE;
return TRUE;
}
/**
Signature dictated by IJG.
*/
static void skip_input_data(
j_decompress_ptr cinfo,
long num_bytes) {
mem_src_ptr src = (mem_src_ptr)cinfo->src;
if (num_bytes > 0) {
while (num_bytes > (long) src->pub.bytes_in_buffer) {
num_bytes -= (long) src->pub.bytes_in_buffer;
boolean s = fill_input_buffer(cinfo);
debugAssert(s); (void)s;
}
src->pub.next_input_byte += (size_t) num_bytes;
src->pub.bytes_in_buffer -= (size_t) num_bytes;
}
}
/**
Signature dictated by IJG.
*/
static void term_source (
j_decompress_ptr cinfo) {
(void)cinfo;
// Intentionally empty
}
/**
Signature dictated by IJG.
*/
static void jpeg_memory_src (
j_decompress_ptr cinfo,
JOCTET* buffer,
int size) {
mem_src_ptr src;
if (cinfo->src == NULL) {
// First time for this JPEG object
cinfo->src = (struct jpeg_source_mgr*)
(*cinfo->mem->alloc_small)(
(j_common_ptr) cinfo,
JPOOL_PERMANENT,
sizeof(memory_source_mgr));
src = (mem_src_ptr)cinfo->src;
src->buffer = (JOCTET*)
(*cinfo->mem->alloc_small)(
(j_common_ptr) cinfo,
JPOOL_PERMANENT,
INPUT_BUF_SIZE * sizeof(JOCTET));
}
src = (mem_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;
// use default method
src->pub.resync_to_restart = jpeg_resync_to_restart;
src->pub.term_source = term_source;
src->source_data = buffer;
src->source_size = size;
// forces fill_input_buffer on first read
src->pub.bytes_in_buffer = 0;
// until buffer loaded
src->pub.next_input_byte = NULL;
}
void GImage::encodeJPEG(
BinaryOutput& out) const {
if (m_channels != 3) {
// Convert to three channel
GImage tmp = *this;
tmp.convertToRGB();
tmp.encodeJPEG(out);
return;
}
debugAssert(m_channels == 3);
out.setEndian(G3D_LITTLE_ENDIAN);
// Allocate and initialize a compression object
jpeg_compress_struct cinfo;
jpeg_error_mgr jerr;
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_compress(&cinfo);
// Specify the destination for the compressed data.
// (Overestimate the size)
int buffer_size = m_width * m_height * 3 + 200;
JOCTET* compressed_data = (JOCTET*)System::malloc(buffer_size);
jpeg_memory_dest(&cinfo, compressed_data, buffer_size);
cinfo.image_width = m_width;
cinfo.image_height = m_height;
// # of color components per pixel
cinfo.input_components = 3;
// colorspace of input image
cinfo.in_color_space = JCS_RGB;
cinfo.input_gamma = 1.0;
// Set parameters for compression, including image size & colorspace
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo, jpegQuality, false);
cinfo.smoothing_factor = 0;
cinfo.optimize_coding = TRUE;
// cinfo.dct_method = JDCT_FLOAT;
cinfo.dct_method = JDCT_ISLOW;
cinfo.jpeg_color_space = JCS_YCbCr;
// Initialize the compressor
jpeg_start_compress(&cinfo, TRUE);
// Iterate over all scanlines from top to bottom
// pointer to a single row
JSAMPROW row_pointer[1];
// JSAMPLEs per row in image_buffer
int row_stride = cinfo.image_width * 3;
while (cinfo.next_scanline < cinfo.image_height) {
row_pointer[0] = &(m_byte[cinfo.next_scanline * row_stride]);
jpeg_write_scanlines(&cinfo, row_pointer, 1);
}
// Shut down the compressor
jpeg_finish_compress(&cinfo);
// Figure out how big the result was.
int outLength = ((mem_dest_ptr)cinfo.dest)->count;
// Release the JPEG compression object
jpeg_destroy_compress(&cinfo);
// Copy into an appropriately sized output buffer.
out.writeBytes(compressed_data, outLength);
// Free the conservative buffer.
System::free(compressed_data);
compressed_data = NULL;
}
void GImage::decodeJPEG(
BinaryInput& input) {
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
int loc = 0;
m_channels = 3;
// We have to set up the error handler, in case initialization fails.
cinfo.err = jpeg_std_error(&jerr);
// Initialize the JPEG decompression object.
jpeg_create_decompress(&cinfo);
// Specify data source (eg, a file, for us, memory)
jpeg_memory_src(&cinfo, const_cast<uint8*>(input.getCArray()), input.size());
// Read the parameters with jpeg_read_header()
jpeg_read_header(&cinfo, TRUE);
// Set parameters for decompression
// (We do nothing here since the defaults are fine)
// Start decompressor
jpeg_start_decompress(&cinfo);
// Get and set the values of interest to this object
m_width = cinfo.output_width;
m_height = cinfo.output_height;
// Prepare the pointer object for the pixel data
m_byte = (uint8*)m_memMan->alloc(m_width * m_height * 3);
// JSAMPLEs per row in output buffer
int bpp = cinfo.output_components;
int row_stride = cinfo.output_width * bpp;
// Make a one-row-high sample array that will go away when done with image
JSAMPARRAY temp = (*cinfo.mem->alloc_sarray)
((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
// Read data on a scanline by scanline basis
while (cinfo.output_scanline < cinfo.output_height) {
// We may need to adjust the output based on the
// number of channels it has.
switch (bpp) {
case 1:
// Grayscale; decompress to temp.
jpeg_read_scanlines(&cinfo, temp, 1);
// Expand to three channels
{
uint8* scan = &(m_byte[loc * 3]);
uint8* endScan = scan + (m_width * 3);
uint8* t = *temp;
while (scan < endScan) {
uint8 value = t[0];
// Spread the value 3x.
scan[0] = value;
scan[1] = value;
scan[2] = value;
scan += 3;
t += 1;
}
}
break;
case 3:
// Read directly into the array
{
// Need one extra level of indirection.
uint8* scan = m_byte + loc;
JSAMPARRAY ptr = &scan;
jpeg_read_scanlines(&cinfo, ptr, 1);
}
break;
case 4:
// RGBA; decompress to temp.
jpeg_read_scanlines(&cinfo, temp, 1);
// Drop the 3rd channel
{
uint8* scan = &(m_byte[loc * 3]);
uint8* endScan = scan + m_width * 3;
uint8* t = *temp;
while (scan < endScan) {
scan[0] = t[0];
scan[1] = t[1];
scan[2] = t[2];
scan += 3;
t += 4;
}
}
break;
default:
throw Error("Unexpected number of channels.", input.getFilename());
}
loc += row_stride;
}
// Finish decompression
jpeg_finish_decompress(&cinfo);
alwaysAssertM(this, "Corrupt GImage");
// Release JPEG decompression object
jpeg_destroy_decompress(&cinfo);
}
}