static void iwopt_try_gray8_binary_trns(struct iw_context *ctx, struct iw_opt_ctx *optctx)
{
int i,j;
const unsigned char *ptr;
unsigned char *ptr2;
unsigned char clr_used[256];
unsigned char key_clr;
unsigned char *trns_mask = NULL;
if(!(ctx->output_profile&IW_PROFILE_BINARYTRNS)) return;
if(!ctx->opt_binary_trns) return;
memset(&clr_used,0,256*sizeof(unsigned char));
trns_mask = iw_malloc_large(ctx, optctx->width, optctx->height);
if(!trns_mask) goto done;
for(j=0;j<optctx->height;j++) {
for(i=0;i<optctx->width;i++) {
ptr = &optctx->pixelsptr[j*optctx->bpr+i*2];
if(ptr[1]==0) {
// Transparent pixel
trns_mask[j*optctx->width+i] = 0;
continue;
}
else {
// Nontransparent pixel
trns_mask[j*optctx->width+i] = 1;
}
clr_used[(int)ptr[0]] = 1;
}
}
if(!iwopt_find_unused(clr_used,256,&key_clr)) {
goto done;
}
// Strip the alpha channel:
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAY,0,0,0);
if(!optctx->tmp_pixels) goto done;
// Change the color of all transparent pixels to the key color
for(j=0;j<optctx->height;j++) {
for(i=0;i<optctx->width;i++) {
ptr2 = &optctx->tmp_pixels[j*optctx->bpr+i];
if(trns_mask[j*optctx->width+i]==0) {
ptr2[0] = key_clr;
}
}
}
optctx->has_colorkey_trns = 1;
optctx->colorkey_r = key_clr;
optctx->colorkey_g = key_clr;
optctx->colorkey_b = key_clr;
done:
if(trns_mask) iw_free(trns_mask);
}
// Strip alpha channel if there are no actual transparent pixels, etc.
void iw_optimize_image(struct iw_context *ctx)
{
struct iw_opt_ctx *optctx;
optctx = &ctx->optctx;
memset(optctx,0,sizeof(struct iw_opt_ctx));
optctx->width = ctx->img2.width;
optctx->height = ctx->img2.height;
optctx->imgtype = ctx->img2.imgtype;
optctx->bit_depth = ctx->img2.bit_depth;
optctx->bpr = ctx->img2.bpr;
optctx->pixelsptr = ctx->img2.pixels;
optctx->has_transparency=0;
optctx->has_partial_transparency=0;
optctx->has_16bit_precision=0;
optctx->has_color=0;
if(ctx->img2.sampletype!=IW_SAMPLETYPE_UINT) {
return;
}
make_transparent_pixels_black(ctx,&ctx->img2);
if(!iw_opt_scanpixels(ctx,optctx)) {
goto noscan;
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,4);
}
if(optctx->imgtype==IW_IMGTYPE_RGB && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,3);
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,2);
}
if(optctx->imgtype==IW_IMGTYPE_GRAY && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,1);
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==8 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_RGB,0,1,2); // RGBA -> RGB
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_RGB,0,1,2); // RGBA -> RGB (16)
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==16 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // GA -> G (16)
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==8 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // GA -> G
}
if(optctx->imgtype==IW_IMGTYPE_RGB && optctx->bit_depth==8 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // RGB -> G
}
if(optctx->imgtype==IW_IMGTYPE_RGB && optctx->bit_depth==16 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // RGB -> G (16)
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==8 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAYA,0,3, 0); // RGBA -> GA
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_GRAYA,0,3, 0); // RGBA -> GA (16)
}
noscan:
iwopt_try_pal_lowgray_optimization(ctx,optctx);
// Try to convert an alpha channel to binary transparency.
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==8 && !optctx->has_partial_transparency) {
iwopt_try_rgb8_binary_trns(ctx,optctx);
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_partial_transparency) {
iwopt_try_rgb16_binary_trns(ctx,optctx);
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==8 && !optctx->has_partial_transparency) {
iwopt_try_gray8_binary_trns(ctx,optctx);
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==16 && !optctx->has_partial_transparency) {
iwopt_try_gray16_binary_trns(ctx,optctx);
}
}
// Try to convert from RGBA to RGB+binary trns.
// Assumes we already know there is transparency, but no partial transparency.
static void iwopt_try_rgb8_binary_trns(struct iw_context *ctx, struct iw_opt_ctx *optctx)
{
int i,j;
const unsigned char *ptr;
unsigned char *ptr2;
unsigned char clr_used[256];
unsigned char key_clr; // Red component of the key color
unsigned char *trns_mask = NULL;
if(!(ctx->output_profile&IW_PROFILE_BINARYTRNS)) return;
if(!ctx->opt_binary_trns) return;
// Try to find a color that's not used in the image.
// Looking for all 2^24 possible colors is too much work.
// We will just look for 256 predefined colors: R={0-255},G=192,B=192
memset(&clr_used,0,256*sizeof(unsigned char));
// Hard to decide how to do this. I don't want the optimization phase
// to modify img2.pixels, though that would be the easiest method.
// Another option would be to make a version of iw_opt_copychannels_8()
// that sets the transparent pixels to a certain value, but that would
// get messy.
// Instead, I'll make a transparency mask, then strip the alpha
// channel, then use the mask to patch up the new image.
trns_mask = iw_malloc_large(ctx, optctx->width, optctx->height);
if(!trns_mask) goto done;
for(j=0;j<optctx->height;j++) {
for(i=0;i<optctx->width;i++) {
ptr = &optctx->pixelsptr[j*optctx->bpr+i*4];
if(ptr[3]==0) {
// transparent pixel
trns_mask[j*optctx->width+i] = 0; // Remember which pixels are transparent.
continue;
}
else {
trns_mask[j*optctx->width+i] = 1;
}
if(ptr[1]!=192 || ptr[2]!=192) continue;
clr_used[(int)ptr[0]] = 1;
}
}
if(!iwopt_find_unused(clr_used,256,&key_clr)) {
goto done;
}
// Strip the alpha channel:
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_RGB,0,1,2);
if(!optctx->tmp_pixels) goto done;
// Change the color of all transparent pixels to the key color
for(j=0;j<optctx->height;j++) {
for(i=0;i<optctx->width;i++) {
ptr2 = &optctx->tmp_pixels[j*optctx->bpr+i*3];
if(trns_mask[j*optctx->width+i]==0) {
ptr2[0] = key_clr;
ptr2[1] = 192;
ptr2[2] = 192;
}
}
}
optctx->has_colorkey_trns = 1;
optctx->colorkey_r = key_clr;
optctx->colorkey_g = 192;
optctx->colorkey_b = 192;
done:
if(trns_mask) iw_free(trns_mask);
}
// Strip alpha channel if there are no actual transparent pixels, etc.
void iwpvt_optimize_image(struct iw_context *ctx)
{
struct iw_opt_ctx *optctx;
int k;
optctx = &ctx->optctx;
//iw_zeromem(optctx,sizeof(struct iw_opt_ctx));
optctx->width = ctx->img2.width;
optctx->height = ctx->img2.height;
optctx->imgtype = ctx->img2.imgtype;
optctx->bit_depth = ctx->img2.bit_depth;
optctx->bpr = ctx->img2.bpr;
optctx->pixelsptr = ctx->img2.pixels;
//optctx->has_transparency=0;
//optctx->has_partial_transparency=0;
//optctx->has_16bit_precision=0;
//optctx->has_color=0;
if(ctx->img2.has_bkgdlabel) {
optctx->has_bkgdlabel = ctx->img2.has_bkgdlabel;
for(k=0;k<4;k++) {
optctx->bkgdlabel[k] = iw_color_get_int_sample(&ctx->img2.bkgdlabel, k,
ctx->img2.bit_depth==8?255:65535);
}
}
if(ctx->img2.sampletype!=IW_SAMPLETYPE_UINT) {
return;
}
if(ctx->reduced_output_maxcolor_flag) {
return;
}
make_transparent_pixels_black(ctx,&ctx->img2);
if(optctx->has_bkgdlabel) {
// The optimization routines are responsible for ensuring that the
// background color label can easily be written to the optimized image.
// For example, they may have to add a color to the palette just for
// the background color.
// They are NOT responsible for telling the image encoder module
// precisely how to write the background color. The encoder will be
// given the background color in RGB format, and it will have to figure
// out what to do with it. For example, it may have to search for that
// color in the palette.
// If the background color label exists, and is non-gray,
// make sure we don't write a grayscale image
// (assuming we're writing to a PNG-like format).
if(optctx->bkgdlabel[0] != optctx->bkgdlabel[1] ||
optctx->bkgdlabel[0] != optctx->bkgdlabel[2])
{
optctx->has_color = 1;
}
// If 16-bit precision is desired, and the background color cannot be
// losslessly reduced to 8-bit precision, use 16-bit precision.
if(optctx->bit_depth==16) {
if(optctx->bkgdlabel[0]%257!=0 || optctx->bkgdlabel[1]%257!=0 ||
optctx->bkgdlabel[2]%257!=0)
{
optctx->has_16bit_precision=1;
}
}
}
if(!iw_opt_scanpixels(ctx,optctx)) {
goto noscan;
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,4);
}
if(optctx->imgtype==IW_IMGTYPE_RGB && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,3);
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,2);
}
if(optctx->imgtype==IW_IMGTYPE_GRAY && optctx->bit_depth==16 && !optctx->has_16bit_precision) {
iw_opt_16_to_8(ctx,optctx,1);
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==8 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_RGB,0,1,2); // RGBA -> RGB
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_RGB,0,1,2); // RGBA -> RGB (16)
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==16 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // GA -> G (16)
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==8 && !optctx->has_transparency && ctx->opt_strip_alpha) {
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // GA -> G
}
if(optctx->imgtype==IW_IMGTYPE_RGB && optctx->bit_depth==8 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // RGB -> G
}
if(optctx->imgtype==IW_IMGTYPE_RGB && optctx->bit_depth==16 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_GRAY,0, 0,0); // RGB -> G (16)
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==8 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_8(ctx,optctx,IW_IMGTYPE_GRAYA,0,3, 0); // RGBA -> GA
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_color &&
(ctx->output_profile&IW_PROFILE_GRAYSCALE) && ctx->opt_grayscale)
{
iw_opt_copychannels_16(ctx,optctx,IW_IMGTYPE_GRAYA,0,3, 0); // RGBA -> GA (16)
}
noscan:
iwopt_try_pal_lowgray_optimization(ctx,optctx);
// Try to convert an alpha channel to binary transparency.
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==8 && !optctx->has_partial_transparency) {
iwopt_try_rgb8_binary_trns(ctx,optctx);
}
if(optctx->imgtype==IW_IMGTYPE_RGBA && optctx->bit_depth==16 && !optctx->has_partial_transparency) {
iwopt_try_rgb16_binary_trns(ctx,optctx);
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==8 && !optctx->has_partial_transparency) {
iwopt_try_gray8_binary_trns(ctx,optctx);
}
if(optctx->imgtype==IW_IMGTYPE_GRAYA && optctx->bit_depth==16 && !optctx->has_partial_transparency) {
iwopt_try_gray16_binary_trns(ctx,optctx);
}
}
