static fz_pixmap *
pdf_image_get_pixmap(fz_context *ctx, fz_image *image_, int w, int h)
{
pdf_image *image = (pdf_image *)image_;
fz_pixmap *tile;
fz_stream *stm;
int l2factor;
pdf_image_key key;
int native_l2factor;
int indexed;
/* Check for 'simple' images which are just pixmaps */
if (image->buffer == NULL)
{
tile = image->tile;
if (!tile)
return NULL;
return fz_keep_pixmap(ctx, tile); /* That's all we can give you! */
}
/* Ensure our expectations for tile size are reasonable */
if (w > image->base.w)
w = image->base.w;
if (h > image->base.h)
h = image->base.h;
/* What is our ideal factor? */
if (w == 0 || h == 0)
l2factor = 0;
else
for (l2factor=0; image->base.w>>(l2factor+1) >= w && image->base.h>>(l2factor+1) >= h && l2factor < 8; l2factor++);
/* Can we find any suitable tiles in the cache? */
key.refs = 1;
key.image = &image->base;
key.l2factor = l2factor;
do
{
tile = fz_find_item(ctx, fz_free_pixmap_imp, &key, &pdf_image_store_type);
if (tile)
return tile;
key.l2factor--;
}
while (key.l2factor >= 0);
/* We need to make a new one. */
native_l2factor = l2factor;
stm = fz_open_image_decomp_stream(ctx, image->buffer, &native_l2factor);
indexed = fz_colorspace_is_indexed(image->base.colorspace);
return decomp_image_from_stream(ctx, stm, image, 0, indexed, l2factor, native_l2factor, 1);
}
static fz_pixmap *
pdf_image_get_pixmap(fz_context *ctx, fz_image *image_, int w, int h)
{
pdf_image *image = (pdf_image *)image_;
fz_pixmap *tile;
fz_stream *stm;
int factor;
pdf_image_key key;
/* Check for 'simple' images which are just pixmaps */
/* SumatraPDF: don't produce additional tiles for preloaded images */
if (image->tile || !image->buffer)
{
tile = image->tile;
if (!tile)
return NULL;
return fz_keep_pixmap(ctx, tile); /* That's all we can give you! */
}
/* Ensure our expectations for tile size are reasonable */
if (w > image->base.w)
w = image->base.w;
if (h > image->base.h)
h = image->base.h;
/* What is our ideal factor? */
if (w == 0 || h == 0)
factor = 1;
else
for (factor=1; image->base.w/(2*factor) >= w && image->base.h/(2*factor) >= h && factor < 8; factor *= 2);
/* Can we find any suitable tiles in the cache? */
key.refs = 1;
key.image = &image->base;
key.factor = factor;
do
{
tile = fz_find_item(ctx, fz_free_pixmap_imp, &key, &pdf_image_store_type);
if (tile)
return tile;
key.factor >>= 1;
}
while (key.factor > 0);
/* We need to make a new one. */
stm = pdf_open_image_decomp_stream(ctx, image->buffer, &image->params, &factor);
return decomp_image_from_stream(ctx, stm, image, 0, 0, factor, 0);
}
static pdf_image *
pdf_load_image_imp(pdf_document *xref, pdf_obj *rdb, pdf_obj *dict, fz_stream *cstm, int forcemask)
{
fz_stream *stm = NULL;
pdf_image *image = NULL;
pdf_obj *obj, *res;
int w, h, bpc, n;
int imagemask;
int interpolate;
int indexed;
fz_image *mask = NULL; /* explicit mask/soft mask image */
int usecolorkey;
int i;
fz_context *ctx = xref->ctx;
fz_var(stm);
fz_var(mask);
image = fz_malloc_struct(ctx, pdf_image);
fz_try(ctx)
{
/* special case for JPEG2000 images */
if (pdf_is_jpx_image(ctx, dict))
{
pdf_load_jpx(xref, dict, image, forcemask);
if (forcemask)
{
fz_pixmap *mask_pixmap;
if (image->n != 2)
fz_throw(ctx, "soft mask must be grayscale");
mask_pixmap = fz_alpha_from_gray(ctx, image->tile, 1);
fz_drop_pixmap(ctx, image->tile);
image->tile = mask_pixmap;
}
break; /* Out of fz_try */
}
w = pdf_to_int(pdf_dict_getsa(dict, "Width", "W"));
h = pdf_to_int(pdf_dict_getsa(dict, "Height", "H"));
bpc = pdf_to_int(pdf_dict_getsa(dict, "BitsPerComponent", "BPC"));
if (bpc == 0)
bpc = 8;
imagemask = pdf_to_bool(pdf_dict_getsa(dict, "ImageMask", "IM"));
interpolate = pdf_to_bool(pdf_dict_getsa(dict, "Interpolate", "I"));
indexed = 0;
usecolorkey = 0;
mask = NULL;
if (imagemask)
bpc = 1;
if (w <= 0)
fz_throw(ctx, "image width is zero (or less)");
if (h <= 0)
fz_throw(ctx, "image height is zero (or less)");
if (bpc <= 0)
fz_throw(ctx, "image depth is zero (or less)");
if (bpc > 16)
fz_throw(ctx, "image depth is too large: %d", bpc);
if (w > (1 << 16))
fz_throw(ctx, "image is too wide");
if (h > (1 << 16))
fz_throw(ctx, "image is too high");
obj = pdf_dict_getsa(dict, "ColorSpace", "CS");
if (obj && !imagemask && !forcemask)
{
/* colorspace resource lookup is only done for inline images */
if (pdf_is_name(obj))
{
res = pdf_dict_get(pdf_dict_gets(rdb, "ColorSpace"), obj);
if (res)
obj = res;
}
image->base.colorspace = pdf_load_colorspace(xref, obj);
if (!strcmp(image->base.colorspace->name, "Indexed"))
indexed = 1;
n = image->base.colorspace->n;
}
else
{
n = 1;
}
obj = pdf_dict_getsa(dict, "Decode", "D");
if (obj)
{
for (i = 0; i < n * 2; i++)
image->decode[i] = pdf_to_real(pdf_array_get(obj, i));
}
else
{
float maxval = indexed ? (1 << bpc) - 1 : 1;
for (i = 0; i < n * 2; i++)
image->decode[i] = i & 1 ? maxval : 0;
}
obj = pdf_dict_getsa(dict, "SMask", "Mask");
if (pdf_is_dict(obj))
{
/* Not allowed for inline images or soft masks */
if (cstm)
fz_warn(ctx, "Ignoring invalid inline image soft mask");
else if (forcemask)
fz_warn(ctx, "Ignoring recursive image soft mask");
else
mask = (fz_image *)pdf_load_image_imp(xref, rdb, obj, NULL, 1);
}
else if (pdf_is_array(obj))
{
usecolorkey = 1;
for (i = 0; i < n * 2; i++)
{
if (!pdf_is_int(pdf_array_get(obj, i)))
{
fz_warn(ctx, "invalid value in color key mask");
usecolorkey = 0;
}
image->colorkey[i] = pdf_to_int(pdf_array_get(obj, i));
}
}
/* Now, do we load a ref, or do we load the actual thing? */
FZ_INIT_STORABLE(&image->base, 1, pdf_free_image);
image->base.get_pixmap = pdf_image_get_pixmap;
image->base.w = w;
image->base.h = h;
image->base.bpc = bpc;
image->n = n;
image->interpolate = interpolate;
image->imagemask = imagemask;
image->usecolorkey = usecolorkey;
image->base.mask = mask;
if (!cstm)
{
/* Just load the compressed image data now and we can
* decode it on demand. */
int num = pdf_to_num(dict);
int gen = pdf_to_gen(dict);
image->buffer = pdf_load_compressed_stream(xref, num, gen);
break; /* Out of fz_try */
}
/* We need to decompress the image now */
if (cstm)
{
int stride = (w * image->n * image->base.bpc + 7) / 8;
stm = pdf_open_inline_stream(xref, dict, stride * h, cstm, NULL);
}
else
{
stm = pdf_open_stream(xref, pdf_to_num(dict), pdf_to_gen(dict));
}
image->tile = decomp_image_from_stream(ctx, stm, image, cstm != NULL, indexed, 0, 0, 0);
}
fz_catch(ctx)
{
pdf_free_image(ctx, (fz_storable *) image);
fz_rethrow(ctx);
}
return image;
}
static fz_pixmap *
decomp_image_banded(fz_context *ctx, fz_stream *stm, pdf_image *image, int indexed, int l2factor, int native_l2factor, int cache)
{
fz_pixmap *tile = NULL, *part = NULL;
int w = (image->base.w + (1 << l2factor) - 1) >> l2factor;
int h = (image->base.h + (1 << l2factor) - 1) >> l2factor;
int part_h, orig_h = image->base.h;
int band = 1 << fz_maxi(8, l2factor);
fz_var(tile);
fz_var(part);
fz_try(ctx)
{
tile = fz_new_pixmap(ctx, image->base.colorspace, w, h);
tile->interpolate = image->interpolate;
tile->has_alpha = 0; /* SumatraPDF: allow optimizing non-alpha pixmaps */
/* decompress the image in bands of 256 lines */
for (part_h = h; part_h > 0; part_h -= band >> l2factor)
{
image->base.h = part_h > band >> l2factor ? band : (orig_h - 1) % band + 1;
part = decomp_image_from_stream(ctx, fz_keep_stream(stm), image, -1, indexed, l2factor, native_l2factor, 0);
memcpy(tile->samples + (h - part_h) * tile->w * tile->n, part->samples, part->h * part->w * part->n);
tile->has_alpha |= part->has_alpha; /* SumatraPDF: allow optimizing non-alpha pixmaps */
fz_drop_pixmap(ctx, part);
part = NULL;
}
/* cf. http://bugs.ghostscript.com/show_bug.cgi?id=693517 */
if (image->usecolorkey && image->base.mask)
pdf_unblend_masked_tile(ctx, tile, image);
}
fz_always(ctx)
{
image->base.h = orig_h;
fz_close(stm);
}
fz_catch(ctx)
{
fz_drop_pixmap(ctx, part);
fz_drop_pixmap(ctx, tile);
fz_rethrow(ctx);
}
if (cache)
{
pdf_image_key *key = NULL;
fz_var(key);
fz_try(ctx)
{
key = fz_malloc_struct(ctx, pdf_image_key);
key->refs = 1;
key->image = fz_keep_image(ctx, &image->base);
key->l2factor = l2factor;
fz_store_item(ctx, key, tile, fz_pixmap_size(ctx, tile), &pdf_image_store_type);
}
fz_always(ctx)
{
pdf_drop_image_key(ctx, key);
}
fz_catch(ctx) { }
}
return tile;
}
