eBookReaderSwitch/mupdf/source/pdf/pdf-image.c

554 lines
15 KiB
C

#include "mupdf/fitz.h"
#include "mupdf/pdf.h"
#include <string.h>
static fz_image *pdf_load_jpx(fz_context *ctx, pdf_document *doc, pdf_obj *dict, int forcemask);
static fz_image *
pdf_load_jpx_imp(fz_context *ctx, pdf_document *doc, pdf_obj *rdb, pdf_obj *dict, fz_stream *cstm, int forcemask)
{
fz_image *image = pdf_load_jpx(ctx, doc, dict, forcemask);
if (forcemask)
{
fz_pixmap_image *cimg = (fz_pixmap_image *)image;
fz_pixmap *mask_pixmap;
fz_pixmap *tile = fz_pixmap_image_tile(ctx, cimg);
if (tile->n != 1)
{
fz_pixmap *gray = fz_convert_pixmap(ctx, tile, fz_device_gray(ctx), NULL, NULL, fz_default_color_params, 0);
fz_drop_pixmap(ctx, tile);
tile = gray;
}
mask_pixmap = fz_alpha_from_gray(ctx, tile);
fz_drop_pixmap(ctx, tile);
fz_set_pixmap_image_tile(ctx, cimg, mask_pixmap);
}
return image;
}
static fz_image *
pdf_load_image_imp(fz_context *ctx, pdf_document *doc, pdf_obj *rdb, pdf_obj *dict, fz_stream *cstm, int forcemask)
{
fz_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 use_colorkey = 0;
fz_colorspace *colorspace = NULL;
float decode[FZ_MAX_COLORS * 2];
int colorkey[FZ_MAX_COLORS * 2];
int stride;
int i;
fz_compressed_buffer *buffer;
/* special case for JPEG2000 images */
if (pdf_is_jpx_image(ctx, dict))
return pdf_load_jpx_imp(ctx, doc, rdb, dict, cstm, forcemask);
w = pdf_to_int(ctx, pdf_dict_geta(ctx, dict, PDF_NAME(Width), PDF_NAME(W)));
h = pdf_to_int(ctx, pdf_dict_geta(ctx, dict, PDF_NAME(Height), PDF_NAME(H)));
bpc = pdf_to_int(ctx, pdf_dict_geta(ctx, dict, PDF_NAME(BitsPerComponent), PDF_NAME(BPC)));
if (bpc == 0)
bpc = 8;
imagemask = pdf_to_bool(ctx, pdf_dict_geta(ctx, dict, PDF_NAME(ImageMask), PDF_NAME(IM)));
interpolate = pdf_to_bool(ctx, pdf_dict_geta(ctx, dict, PDF_NAME(Interpolate), PDF_NAME(I)));
indexed = 0;
use_colorkey = 0;
if (imagemask)
bpc = 1;
if (w <= 0)
fz_throw(ctx, FZ_ERROR_GENERIC, "image width is zero (or less)");
if (h <= 0)
fz_throw(ctx, FZ_ERROR_GENERIC, "image height is zero (or less)");
if (bpc <= 0)
fz_throw(ctx, FZ_ERROR_GENERIC, "image depth is zero (or less)");
if (bpc > 16)
fz_throw(ctx, FZ_ERROR_GENERIC, "image depth is too large: %d", bpc);
if (w > (1 << 16))
fz_throw(ctx, FZ_ERROR_GENERIC, "image is too wide");
if (h > (1 << 16))
fz_throw(ctx, FZ_ERROR_GENERIC, "image is too high");
fz_var(mask);
fz_var(image);
fz_var(colorspace);
fz_try(ctx)
{
obj = pdf_dict_geta(ctx, dict, PDF_NAME(ColorSpace), PDF_NAME(CS));
if (obj && !imagemask && !forcemask)
{
/* colorspace resource lookup is only done for inline images */
if (pdf_is_name(ctx, obj))
{
res = pdf_dict_get(ctx, pdf_dict_get(ctx, rdb, PDF_NAME(ColorSpace)), obj);
if (res)
obj = res;
}
colorspace = pdf_load_colorspace(ctx, obj);
indexed = fz_colorspace_is_indexed(ctx, colorspace);
n = fz_colorspace_n(ctx, colorspace);
}
else
{
n = 1;
}
obj = pdf_dict_geta(ctx, dict, PDF_NAME(Decode), PDF_NAME(D));
if (obj)
{
for (i = 0; i < n * 2; i++)
decode[i] = pdf_array_get_real(ctx, obj, i);
}
else if (fz_colorspace_is_lab(ctx, colorspace))
{
decode[0] = 0;
decode[1] = 100;
decode[2] = -128;
decode[3] = 127;
decode[4] = -128;
decode[5] = 127;
}
else
{
float maxval = indexed ? (1 << bpc) - 1 : 1;
for (i = 0; i < n * 2; i++)
decode[i] = i & 1 ? maxval : 0;
}
obj = pdf_dict_geta(ctx, dict, PDF_NAME(SMask), PDF_NAME(Mask));
if (pdf_is_dict(ctx, 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 = pdf_load_image_imp(ctx, doc, rdb, obj, NULL, 1);
obj = pdf_dict_get(ctx, obj, PDF_NAME(Matte));
if (pdf_is_array(ctx, obj))
{
use_colorkey = 1;
for (i = 0; i < n; i++)
colorkey[i] = pdf_array_get_real(ctx, obj, i) * 255;
}
}
}
else if (pdf_is_array(ctx, obj))
{
use_colorkey = 1;
for (i = 0; i < n * 2; i++)
{
if (!pdf_is_int(ctx, pdf_array_get(ctx, obj, i)))
{
fz_warn(ctx, "invalid value in color key mask");
use_colorkey = 0;
}
colorkey[i] = pdf_array_get_int(ctx, obj, i);
}
}
/* Do we load from a ref, or do we load an inline stream? */
if (cstm == NULL)
{
/* Just load the compressed image data now and we can decode it on demand. */
buffer = pdf_load_compressed_stream(ctx, doc, pdf_to_num(ctx, dict));
image = fz_new_image_from_compressed_buffer(ctx, w, h, bpc, colorspace, 96, 96, interpolate, imagemask, decode, use_colorkey ? colorkey : NULL, buffer, mask);
image->invert_cmyk_jpeg = 0;
}
else
{
/* Inline stream */
stride = (w * n * bpc + 7) / 8;
image = fz_new_image_from_compressed_buffer(ctx, w, h, bpc, colorspace, 96, 96, interpolate, imagemask, decode, use_colorkey ? colorkey : NULL, NULL, mask);
image->invert_cmyk_jpeg = 0;
pdf_load_compressed_inline_image(ctx, doc, dict, stride * h, cstm, indexed, (fz_compressed_image *)image);
}
}
fz_always(ctx)
{
fz_drop_colorspace(ctx, colorspace);
fz_drop_image(ctx, mask);
}
fz_catch(ctx)
{
fz_drop_image(ctx, image);
fz_rethrow(ctx);
}
return image;
}
fz_image *
pdf_load_inline_image(fz_context *ctx, pdf_document *doc, pdf_obj *rdb, pdf_obj *dict, fz_stream *file)
{
return pdf_load_image_imp(ctx, doc, rdb, dict, file, 0);
}
int
pdf_is_jpx_image(fz_context *ctx, pdf_obj *dict)
{
pdf_obj *filter;
int i, n;
filter = pdf_dict_get(ctx, dict, PDF_NAME(Filter));
if (pdf_name_eq(ctx, filter, PDF_NAME(JPXDecode)))
return 1;
n = pdf_array_len(ctx, filter);
for (i = 0; i < n; i++)
if (pdf_name_eq(ctx, pdf_array_get(ctx, filter, i), PDF_NAME(JPXDecode)))
return 1;
return 0;
}
static fz_image *
pdf_load_jpx(fz_context *ctx, pdf_document *doc, pdf_obj *dict, int forcemask)
{
fz_buffer *buf = NULL;
fz_colorspace *colorspace = NULL;
fz_pixmap *pix = NULL;
pdf_obj *obj;
fz_image *mask = NULL;
fz_image *img = NULL;
fz_var(pix);
fz_var(buf);
fz_var(colorspace);
fz_var(mask);
buf = pdf_load_stream(ctx, dict);
/* FIXME: We can't handle decode arrays for indexed images currently */
fz_try(ctx)
{
unsigned char *data;
size_t len;
obj = pdf_dict_get(ctx, dict, PDF_NAME(ColorSpace));
if (obj)
colorspace = pdf_load_colorspace(ctx, obj);
len = fz_buffer_storage(ctx, buf, &data);
pix = fz_load_jpx(ctx, data, len, colorspace);
obj = pdf_dict_geta(ctx, dict, PDF_NAME(SMask), PDF_NAME(Mask));
if (pdf_is_dict(ctx, obj))
{
if (forcemask)
fz_warn(ctx, "Ignoring recursive JPX soft mask");
else
mask = pdf_load_image_imp(ctx, doc, NULL, obj, NULL, 1);
}
obj = pdf_dict_geta(ctx, dict, PDF_NAME(Decode), PDF_NAME(D));
if (obj && !fz_colorspace_is_indexed(ctx, colorspace))
{
float decode[FZ_MAX_COLORS * 2];
int i;
for (i = 0; i < pix->n * 2; i++)
decode[i] = pdf_array_get_real(ctx, obj, i);
fz_decode_tile(ctx, pix, decode);
}
img = fz_new_image_from_pixmap(ctx, pix, mask);
}
fz_always(ctx)
{
fz_drop_image(ctx, mask);
fz_drop_pixmap(ctx, pix);
fz_drop_colorspace(ctx, colorspace);
fz_drop_buffer(ctx, buf);
}
fz_catch(ctx)
{
fz_rethrow(ctx);
}
return img;
}
fz_image *
pdf_load_image(fz_context *ctx, pdf_document *doc, pdf_obj *dict)
{
fz_image *image;
if ((image = pdf_find_item(ctx, fz_drop_image_imp, dict)) != NULL)
return image;
image = pdf_load_image_imp(ctx, doc, NULL, dict, NULL, 0);
pdf_store_item(ctx, dict, image, fz_image_size(ctx, image));
return image;
}
pdf_obj *
pdf_add_image(fz_context *ctx, pdf_document *doc, fz_image *image)
{
fz_pixmap *pixmap = NULL;
pdf_obj *imobj = NULL;
pdf_obj *dp;
fz_buffer *buffer = NULL;
pdf_obj *imref = NULL;
fz_compressed_buffer *cbuffer;
unsigned char digest[16];
int i, n;
/* If we can maintain compression, do so */
cbuffer = fz_compressed_image_buffer(ctx, image);
fz_var(pixmap);
fz_var(buffer);
fz_var(imobj);
fz_var(imref);
/* Check if the same image already exists in this doc. */
imref = pdf_find_image_resource(ctx, doc, image, digest);
if (imref)
return imref;
imobj = pdf_add_new_dict(ctx, doc, 3);
fz_try(ctx)
{
dp = pdf_dict_put_dict(ctx, imobj, PDF_NAME(DecodeParms), 3);
pdf_dict_put(ctx, imobj, PDF_NAME(Type), PDF_NAME(XObject));
pdf_dict_put(ctx, imobj, PDF_NAME(Subtype), PDF_NAME(Image));
if (cbuffer)
{
fz_compression_params *cp = &cbuffer->params;
switch (cp ? cp->type : FZ_IMAGE_UNKNOWN)
{
default:
goto raw_or_unknown_compression;
case FZ_IMAGE_JPEG:
if (cp->u.jpeg.color_transform != -1)
pdf_dict_put_int(ctx, dp, PDF_NAME(ColorTransform), cp->u.jpeg.color_transform);
pdf_dict_put(ctx, imobj, PDF_NAME(Filter), PDF_NAME(DCTDecode));
break;
case FZ_IMAGE_JPX:
if (cp->u.jpx.smask_in_data)
pdf_dict_put_int(ctx, dp, PDF_NAME(SMaskInData), cp->u.jpx.smask_in_data);
pdf_dict_put(ctx, imobj, PDF_NAME(Filter), PDF_NAME(JPXDecode));
break;
case FZ_IMAGE_FAX:
if (cp->u.fax.columns)
pdf_dict_put_int(ctx, dp, PDF_NAME(Columns), cp->u.fax.columns);
if (cp->u.fax.rows)
pdf_dict_put_int(ctx, dp, PDF_NAME(Rows), cp->u.fax.rows);
if (cp->u.fax.k)
pdf_dict_put_int(ctx, dp, PDF_NAME(K), cp->u.fax.k);
if (cp->u.fax.end_of_line)
pdf_dict_put_bool(ctx, dp, PDF_NAME(EndOfLine), cp->u.fax.end_of_line);
if (cp->u.fax.encoded_byte_align)
pdf_dict_put_bool(ctx, dp, PDF_NAME(EncodedByteAlign), cp->u.fax.encoded_byte_align);
if (cp->u.fax.end_of_block)
pdf_dict_put_bool(ctx, dp, PDF_NAME(EndOfBlock), cp->u.fax.end_of_block);
if (cp->u.fax.black_is_1)
pdf_dict_put_bool(ctx, dp, PDF_NAME(BlackIs1), cp->u.fax.black_is_1);
if (cp->u.fax.damaged_rows_before_error)
pdf_dict_put_int(ctx, dp, PDF_NAME(DamagedRowsBeforeError), cp->u.fax.damaged_rows_before_error);
pdf_dict_put(ctx, imobj, PDF_NAME(Filter), PDF_NAME(CCITTFaxDecode));
break;
case FZ_IMAGE_FLATE:
if (cp->u.flate.columns)
pdf_dict_put_int(ctx, dp, PDF_NAME(Columns), cp->u.flate.columns);
if (cp->u.flate.colors)
pdf_dict_put_int(ctx, dp, PDF_NAME(Colors), cp->u.flate.colors);
if (cp->u.flate.predictor)
pdf_dict_put_int(ctx, dp, PDF_NAME(Predictor), cp->u.flate.predictor);
if (cp->u.flate.bpc)
pdf_dict_put_int(ctx, dp, PDF_NAME(BitsPerComponent), cp->u.flate.bpc);
pdf_dict_put(ctx, imobj, PDF_NAME(Filter), PDF_NAME(FlateDecode));
pdf_dict_put_int(ctx, imobj, PDF_NAME(BitsPerComponent), image->bpc);
break;
case FZ_IMAGE_LZW:
if (cp->u.lzw.columns)
pdf_dict_put_int(ctx, dp, PDF_NAME(Columns), cp->u.lzw.columns);
if (cp->u.lzw.colors)
pdf_dict_put_int(ctx, dp, PDF_NAME(Colors), cp->u.lzw.colors);
if (cp->u.lzw.predictor)
pdf_dict_put_int(ctx, dp, PDF_NAME(Predictor), cp->u.lzw.predictor);
if (cp->u.lzw.early_change)
pdf_dict_put_int(ctx, dp, PDF_NAME(EarlyChange), cp->u.lzw.early_change);
if (cp->u.lzw.bpc)
pdf_dict_put_int(ctx, dp, PDF_NAME(BitsPerComponent), cp->u.lzw.bpc);
pdf_dict_put(ctx, imobj, PDF_NAME(Filter), PDF_NAME(LZWDecode));
break;
case FZ_IMAGE_RLD:
pdf_dict_put(ctx, imobj, PDF_NAME(Filter), PDF_NAME(RunLengthDecode));
break;
}
if (!pdf_dict_len(ctx, dp))
pdf_dict_del(ctx, imobj, PDF_NAME(DecodeParms));
buffer = fz_keep_buffer(ctx, cbuffer->buffer);
if (image->use_decode)
{
pdf_obj *ary = pdf_dict_put_array(ctx, imobj, PDF_NAME(Decode), image->n * 2);
for (i = 0; i < image->n * 2; ++i)
pdf_array_push_real(ctx, ary, image->decode[i]);
}
}
else
{
unsigned int size;
int h;
unsigned char *d, *s;
raw_or_unknown_compression:
/* Currently, set to maintain resolution; should we consider
* subsampling here according to desired output res? */
pixmap = fz_get_pixmap_from_image(ctx, image, NULL, NULL, NULL, NULL);
n = pixmap->n - pixmap->alpha - pixmap->s; /* number of colorants */
if (n == 0)
n = 1; /* treat pixmaps with only alpha or spots as grayscale */
size = image->w * n;
h = image->h;
s = pixmap->samples;
d = fz_malloc(ctx, size * h);
buffer = fz_new_buffer_from_data(ctx, d, size * h);
if (n == pixmap->n)
{
/* If we use all channels, we can copy the data as is. */
while (h--)
{
memcpy(d, s, size);
d += size;
s += pixmap->stride;
}
}
else
{
/* Need to remove the alpha and spot planes. */
/* TODO: extract alpha plane to a soft mask. */
/* TODO: convert spots to colors. */
int line_skip = pixmap->stride - pixmap->w * pixmap->n;
int skip = pixmap->n - n;
while (h--)
{
int w = pixmap->w;
while (w--)
{
int k;
for (k = 0; k < n; ++k)
*d++ = *s++;
s += skip;
}
s += line_skip;
}
}
}
pdf_dict_put_int(ctx, imobj, PDF_NAME(Width), pixmap ? pixmap->w : image->w);
pdf_dict_put_int(ctx, imobj, PDF_NAME(Height), pixmap ? pixmap->h : image->h);
if (image->imagemask)
{
pdf_dict_put_bool(ctx, imobj, PDF_NAME(ImageMask), 1);
}
else
{
fz_colorspace *cs;
pdf_dict_put_int(ctx, imobj, PDF_NAME(BitsPerComponent), image->bpc);
cs = pixmap ? pixmap->colorspace : image->colorspace;
switch (fz_colorspace_type(ctx, cs))
{
case FZ_COLORSPACE_INDEXED:
{
fz_colorspace *basecs;
unsigned char *lookup = NULL;
int high = 0;
int basen;
pdf_obj *arr;
basecs = cs->u.indexed.base;
high = cs->u.indexed.high;
lookup = cs->u.indexed.lookup;
basen = basecs->n;
arr = pdf_dict_put_array(ctx, imobj, PDF_NAME(ColorSpace), 4);
pdf_array_push(ctx, arr, PDF_NAME(Indexed));
switch (fz_colorspace_type(ctx, basecs))
{
case FZ_COLORSPACE_GRAY:
pdf_array_push(ctx, arr, PDF_NAME(DeviceGray));
break;
case FZ_COLORSPACE_RGB:
pdf_array_push(ctx, arr, PDF_NAME(DeviceRGB));
break;
case FZ_COLORSPACE_CMYK:
pdf_array_push(ctx, arr, PDF_NAME(DeviceCMYK));
break;
default:
// TODO: convert to RGB!
fz_throw(ctx, FZ_ERROR_GENERIC, "only indexed Gray, RGB, and CMYK colorspaces supported");
break;
}
pdf_array_push_int(ctx, arr, high);
pdf_array_push_string(ctx, arr, (char *) lookup, basen * (high + 1));
}
break;
case FZ_COLORSPACE_NONE:
case FZ_COLORSPACE_GRAY:
pdf_dict_put(ctx, imobj, PDF_NAME(ColorSpace), PDF_NAME(DeviceGray));
break;
case FZ_COLORSPACE_RGB:
pdf_dict_put(ctx, imobj, PDF_NAME(ColorSpace), PDF_NAME(DeviceRGB));
break;
case FZ_COLORSPACE_CMYK:
pdf_dict_put(ctx, imobj, PDF_NAME(ColorSpace), PDF_NAME(DeviceCMYK));
break;
default:
// TODO: convert to RGB!
fz_throw(ctx, FZ_ERROR_GENERIC, "only Gray, RGB, and CMYK colorspaces supported");
break;
}
}
if (image->mask)
{
pdf_dict_put_drop(ctx, imobj, PDF_NAME(SMask), pdf_add_image(ctx, doc, image->mask));
}
pdf_update_stream(ctx, doc, imobj, buffer, 1);
/* Add ref to our image resource hash table. */
imref = pdf_insert_image_resource(ctx, doc, digest, imobj);
}
fz_always(ctx)
{
fz_drop_pixmap(ctx, pixmap);
fz_drop_buffer(ctx, buffer);
pdf_drop_obj(ctx, imobj);
}
fz_catch(ctx)
fz_rethrow(ctx);
return imref;
}