static void
fz_decode_tiff_lzw(fz_context *ctx, struct tiff *tiff, fz_stream *chain, unsigned char *wp, int wlen)
{
fz_stream *stm = fz_open_lzwd(ctx, chain, 1);
fz_read(ctx, stm, wp, wlen);
fz_drop_stream(ctx, stm);
}
static void
fz_decode_tiff_lzw(struct tiff *tiff, fz_stream *chain, unsigned char *wp, int wlen)
{
fz_stream *stm = fz_open_lzwd(chain, 1);
fz_read(stm, wp, wlen);
fz_close(stm);
}
static int
xps_decode_tiff_lzw(struct tiff *tiff, fz_stream *chain, byte *wp, int wlen)
{
fz_stream *stm = fz_open_lzwd(chain, NULL);
int n = fz_read(stm, wp, wlen);
fz_close(stm);
if (n < 0)
return fz_error_note(chain->ctx, n, "cannot read lzw strip");
return fz_okay;
}
fz_stream *
fz_open_image_decomp_stream(fz_context *ctx, fz_compressed_buffer *buffer, int *factor)
{
fz_stream *chain = fz_open_buffer(ctx, buffer->buffer);
fz_compression_params *params = &buffer->params;
switch (params->type)
{
case FZ_IMAGE_FAX:
*factor = 1;
return fz_open_faxd(chain,
params->u.fax.k,
params->u.fax.end_of_line,
params->u.fax.encoded_byte_align,
params->u.fax.columns,
params->u.fax.rows,
params->u.fax.end_of_block,
params->u.fax.black_is_1);
case FZ_IMAGE_JPEG:
if (*factor > 8)
*factor = 8;
return fz_open_resized_dctd(chain, params->u.jpeg.color_transform, *factor);
case FZ_IMAGE_RLD:
*factor = 1;
return fz_open_rld(chain);
case FZ_IMAGE_FLATE:
*factor = 1;
chain = fz_open_flated(chain);
if (params->u.flate.predictor > 1)
chain = fz_open_predict(chain, params->u.flate.predictor, params->u.flate.columns, params->u.flate.colors, params->u.flate.bpc);
return chain;
case FZ_IMAGE_LZW:
*factor = 1;
chain = fz_open_lzwd(chain, params->u.lzw.early_change);
if (params->u.lzw.predictor > 1)
chain = fz_open_predict(chain, params->u.lzw.predictor, params->u.lzw.columns, params->u.lzw.colors, params->u.lzw.bpc);
return chain;
default:
*factor = 1;
break;
}
return chain;
}
fz_stream *
fz_open_image_decomp_stream(fz_context *ctx, fz_stream *chain, fz_compression_params *params, int *l2factor)
{
int our_l2factor = 0;
switch (params->type)
{
case FZ_IMAGE_FAX:
return fz_open_faxd(ctx, chain,
params->u.fax.k,
params->u.fax.end_of_line,
params->u.fax.encoded_byte_align,
params->u.fax.columns,
params->u.fax.rows,
params->u.fax.end_of_block,
params->u.fax.black_is_1);
case FZ_IMAGE_JPEG:
if (l2factor)
{
our_l2factor = *l2factor;
if (our_l2factor > 3)
our_l2factor = 3;
*l2factor -= our_l2factor;
}
return fz_open_dctd(ctx, chain, params->u.jpeg.color_transform, our_l2factor, NULL);
case FZ_IMAGE_RLD:
return fz_open_rld(ctx, chain);
case FZ_IMAGE_FLATE:
chain = fz_open_flated(ctx, chain, 15);
if (params->u.flate.predictor > 1)
chain = fz_open_predict(ctx, chain, params->u.flate.predictor, params->u.flate.columns, params->u.flate.colors, params->u.flate.bpc);
return chain;
case FZ_IMAGE_LZW:
chain = fz_open_lzwd(ctx, chain, params->u.lzw.early_change);
if (params->u.lzw.predictor > 1)
chain = fz_open_predict(ctx, chain, params->u.lzw.predictor, params->u.lzw.columns, params->u.lzw.colors, params->u.lzw.bpc);
return chain;
default:
break;
}
return chain;
}
fz_stream *
pdf_open_image_decomp_stream(fz_context *ctx, fz_buffer *buffer, pdf_image_params *params, int *factor)
{
fz_stream *chain = fz_open_buffer(ctx, buffer);
switch (params->type)
{
case PDF_IMAGE_FAX:
*factor = 1;
return fz_open_faxd(chain,
params->u.fax.k,
params->u.fax.eol,
params->u.fax.eba,
params->u.fax.columns,
params->u.fax.rows,
params->u.fax.eob,
params->u.fax.bi1);
case PDF_IMAGE_JPEG:
if (*factor > 8)
*factor = 8;
return fz_open_resized_dctd(chain, params->u.jpeg.ct, *factor);
case PDF_IMAGE_RLD:
*factor = 1;
return fz_open_rld(chain);
case PDF_IMAGE_FLATE:
*factor = 1;
chain = fz_open_flated(chain);
if (params->u.flate.predictor > 1)
chain = fz_open_predict(chain, params->u.flate.predictor, params->u.flate.columns, params->u.flate.colors, params->u.flate.bpc);
return chain;
case PDF_IMAGE_LZW:
*factor = 1;
chain = fz_open_lzwd(chain, params->u.lzw.ec);
if (params->u.lzw.predictor > 1)
chain = fz_open_predict(chain, params->u.lzw.predictor, params->u.lzw.columns, params->u.lzw.colors, params->u.lzw.bpc);
return chain;
default:
*factor = 1;
break;
}
return chain;
}
/*
* Create a filter given a name and param dictionary.
*/
static fz_stream *
build_filter(fz_stream *chain, pdf_document * xref, pdf_obj * f, pdf_obj * p, int num, int gen, pdf_image_params *params)
{
fz_context *ctx = chain->ctx;
char *s = pdf_to_name(f);
int predictor = pdf_to_int(pdf_dict_gets(p, "Predictor"));
int columns = pdf_to_int(pdf_dict_gets(p, "Columns"));
int colors = pdf_to_int(pdf_dict_gets(p, "Colors"));
int bpc = pdf_to_int(pdf_dict_gets(p, "BitsPerComponent"));
if (predictor == 0) predictor = 1;
if (columns == 0) columns = 1;
if (colors == 0) colors = 1;
if (bpc == 0) bpc = 8;
if (!strcmp(s, "ASCIIHexDecode") || !strcmp(s, "AHx"))
return fz_open_ahxd(chain);
else if (!strcmp(s, "ASCII85Decode") || !strcmp(s, "A85"))
return fz_open_a85d(chain);
else if (!strcmp(s, "CCITTFaxDecode") || !strcmp(s, "CCF"))
{
pdf_obj *k = pdf_dict_gets(p, "K");
pdf_obj *eol = pdf_dict_gets(p, "EndOfLine");
pdf_obj *eba = pdf_dict_gets(p, "EncodedByteAlign");
pdf_obj *columns = pdf_dict_gets(p, "Columns");
pdf_obj *rows = pdf_dict_gets(p, "Rows");
pdf_obj *eob = pdf_dict_gets(p, "EndOfBlock");
pdf_obj *bi1 = pdf_dict_gets(p, "BlackIs1");
if (params)
{
/* We will shortstop here */
params->type = PDF_IMAGE_FAX;
params->u.fax.k = (k ? pdf_to_int(k) : 0);
params->u.fax.eol = (eol ? pdf_to_bool(eol) : 0);
params->u.fax.eba = (eba ? pdf_to_bool(eba) : 0);
params->u.fax.columns = (columns ? pdf_to_int(columns) : 1728);
params->u.fax.rows = (rows ? pdf_to_int(rows) : 0);
params->u.fax.eob = (eob ? pdf_to_bool(eob) : 1);
params->u.fax.bi1 = (bi1 ? pdf_to_bool(bi1) : 0);
return chain;
}
return fz_open_faxd(chain,
k ? pdf_to_int(k) : 0,
eol ? pdf_to_bool(eol) : 0,
eba ? pdf_to_bool(eba) : 0,
columns ? pdf_to_int(columns) : 1728,
rows ? pdf_to_int(rows) : 0,
eob ? pdf_to_bool(eob) : 1,
bi1 ? pdf_to_bool(bi1) : 0);
}
else if (!strcmp(s, "DCTDecode") || !strcmp(s, "DCT"))
{
pdf_obj *ct = pdf_dict_gets(p, "ColorTransform");
if (params)
{
/* We will shortstop here */
params->type = PDF_IMAGE_JPEG;
params->u.jpeg.ct = (ct ? pdf_to_int(ct) : -1);
return chain;
}
return fz_open_dctd(chain, ct ? pdf_to_int(ct) : -1);
}
else if (!strcmp(s, "RunLengthDecode") || !strcmp(s, "RL"))
{
if (params)
{
/* We will shortstop here */
params->type = PDF_IMAGE_RLD;
return chain;
}
return fz_open_rld(chain);
}
else if (!strcmp(s, "FlateDecode") || !strcmp(s, "Fl"))
{
if (params)
{
/* We will shortstop here */
params->type = PDF_IMAGE_FLATE;
params->u.flate.predictor = predictor;
params->u.flate.columns = columns;
params->u.flate.colors = colors;
params->u.flate.bpc = bpc;
return chain;
}
chain = fz_open_flated(chain);
if (predictor > 1)
chain = fz_open_predict(chain, predictor, columns, colors, bpc);
return chain;
}
else if (!strcmp(s, "LZWDecode") || !strcmp(s, "LZW"))
{
pdf_obj *ec = pdf_dict_gets(p, "EarlyChange");
if (params)
{
/* We will shortstop here */
params->type = PDF_IMAGE_LZW;
params->u.lzw.predictor = predictor;
params->u.lzw.columns = columns;
params->u.lzw.colors = colors;
params->u.lzw.bpc = bpc;
params->u.lzw.ec = (ec ? pdf_to_int(ec) : 1);
return chain;
}
chain = fz_open_lzwd(chain, ec ? pdf_to_int(ec) : 1);
if (predictor > 1)
chain = fz_open_predict(chain, predictor, columns, colors, bpc);
return chain;
}
else if (!strcmp(s, "JBIG2Decode"))
{
fz_buffer *globals = NULL;
pdf_obj *obj = pdf_dict_gets(p, "JBIG2Globals");
if (obj)
globals = pdf_load_stream(xref, pdf_to_num(obj), pdf_to_gen(obj));
/* fz_open_jbig2d takes possession of globals */
return fz_open_jbig2d(chain, globals);
}
else if (!strcmp(s, "JPXDecode"))
return chain; /* JPX decoding is special cased in the image loading code */
else if (!strcmp(s, "Crypt"))
{
pdf_obj *name;
if (!xref->crypt)
{
fz_warn(ctx, "crypt filter in unencrypted document");
return chain;
}
name = pdf_dict_gets(p, "Name");
if (pdf_is_name(name))
return pdf_open_crypt_with_filter(chain, xref->crypt, pdf_to_name(name), num, gen);
return chain;
}
fz_warn(ctx, "unknown filter name (%s)", s);
return chain;
}
static unsigned char *
gif_read_tbid(fz_context *ctx, struct info *info, unsigned char *dest, unsigned char *p, unsigned char *end)
{
fz_stream *stm, *lzwstm = NULL;
unsigned int mincodesize, y;
fz_buffer *compressed = NULL, *uncompressed = NULL;
const unsigned char *ct;
unsigned char *sp;
if (end - p < 1)
fz_throw(ctx, FZ_ERROR_GENERIC, "premature end in table based image data in gif image");
mincodesize = *p;
fz_var(compressed);
fz_var(lzwstm);
fz_var(uncompressed);
fz_try(ctx)
{
compressed = fz_new_buffer(ctx, 0);
p = gif_read_subblocks(ctx, info, p + 1, end, compressed);
stm = fz_open_buffer(ctx, compressed);
lzwstm = fz_open_lzwd(ctx, stm, 0, mincodesize + 1, 1, 0);
uncompressed = fz_read_all(ctx, lzwstm, info->width * info->height);
sp = uncompressed->data;
if (info->has_lct)
ct = info->lct;
else if (info->has_gct)
ct = info->gct;
else
ct = dct;
if (info->image_interlaced)
{
for (y = 0; y < info->image_height; y += 8, sp += info->image_width)
gif_read_line(ctx, info, dest, ct, y, sp);
for (y = 4; y < info->image_height; y += 8, sp += info->image_width)
gif_read_line(ctx, info, dest, ct, y, sp);
for (y = 2; y < info->image_height; y += 4, sp += info->image_width)
gif_read_line(ctx, info, dest, ct, y, sp);
for (y = 1; y < info->image_height; y += 2, sp += info->image_width)
gif_read_line(ctx, info, dest, ct, y, sp);
}
else
for (y = 0; y < info->image_height; y++, sp += info->image_width)
gif_read_line(ctx, info, dest, ct, y, sp);
}
fz_always(ctx)
{
fz_drop_buffer(ctx, uncompressed);
fz_drop_buffer(ctx, compressed);
fz_drop_stream(ctx, lzwstm);
}
fz_catch(ctx)
{
fz_rethrow(ctx);
}
return p;
}
static const unsigned char *
gif_read_tbid(fz_context *ctx, struct info *info, unsigned char *dest, const unsigned char *p, const unsigned char *end)
{
fz_stream *stm, *lzwstm = NULL;
unsigned int mincodesize, y;
fz_buffer *compressed = NULL, *uncompressed = NULL;
const unsigned char *ct;
unsigned char *sp;
int ct_entries;
if (end - p < 1)
fz_throw(ctx, FZ_ERROR_GENERIC, "premature end in table based image data in gif image");
mincodesize = *p;
/* if there is no overlap, avoid pasting image data, just consume it */
if (info->image_top >= info->height || info->image_left >= info->width)
{
p = gif_read_subblocks(ctx, info, p + 1, end, NULL);
return p;
}
fz_var(compressed);
fz_var(lzwstm);
fz_var(uncompressed);
fz_try(ctx)
{
compressed = fz_new_buffer(ctx, 0);
p = gif_read_subblocks(ctx, info, p + 1, end, compressed);
stm = fz_open_buffer(ctx, compressed);
lzwstm = fz_open_lzwd(ctx, stm, 0, mincodesize + 1, 1, 1);
uncompressed = fz_read_all(ctx, lzwstm, 0);
if (uncompressed->len < info->image_width * info->image_height)
fz_throw(ctx, FZ_ERROR_GENERIC, "premature end in compressed table based image data in gif image");
if (info->has_lct)
{
ct = info->lct;
ct_entries = info->lct_entries;
}
else if (info->has_gct)
{
ct = info->gct;
ct_entries = info->gct_entries;
}
else
{
ct = dct;
ct_entries = 256;
}
sp = uncompressed->data;
if (info->image_interlaced)
{
for (y = 0; y < info->image_height; y += 8, sp += info->image_width)
gif_read_line(ctx, info, dest, ct_entries, ct, y, sp);
for (y = 4; y < info->image_height; y += 8, sp += info->image_width)
gif_read_line(ctx, info, dest, ct_entries, ct, y, sp);
for (y = 2; y < info->image_height; y += 4, sp += info->image_width)
gif_read_line(ctx, info, dest, ct_entries, ct, y, sp);
for (y = 1; y < info->image_height; y += 2, sp += info->image_width)
gif_read_line(ctx, info, dest, ct_entries, ct, y, sp);
}
else
for (y = 0; y < info->image_height; y++, sp += info->image_width)
gif_read_line(ctx, info, dest, ct_entries, ct, y, sp);
}
fz_always(ctx)
{
fz_drop_buffer(ctx, uncompressed);
fz_drop_buffer(ctx, compressed);
fz_drop_stream(ctx, lzwstm);
}
fz_catch(ctx)
{
fz_rethrow(ctx);
}
return p;
}
/*
* Create a filter given a name and param dictionary.
*/
static fz_stream *
build_filter(fz_stream *chain, pdf_xref * xref, fz_obj * f, fz_obj * p, int num, int gen)
{
fz_error error;
char *s;
s = fz_to_name(f);
if (!strcmp(s, "ASCIIHexDecode") || !strcmp(s, "AHx"))
return fz_open_ahxd(chain);
else if (!strcmp(s, "ASCII85Decode") || !strcmp(s, "A85"))
return fz_open_a85d(chain);
else if (!strcmp(s, "CCITTFaxDecode") || !strcmp(s, "CCF"))
return fz_open_faxd(chain, p);
else if (!strcmp(s, "DCTDecode") || !strcmp(s, "DCT"))
return fz_open_dctd(chain, p);
else if (!strcmp(s, "RunLengthDecode") || !strcmp(s, "RL"))
return fz_open_rld(chain);
else if (!strcmp(s, "FlateDecode") || !strcmp(s, "Fl"))
{
fz_obj *obj = fz_dict_gets(p, "Predictor");
if (fz_to_int(obj) > 1)
return fz_open_predict(fz_open_flated(chain), p);
return fz_open_flated(chain);
}
else if (!strcmp(s, "LZWDecode") || !strcmp(s, "LZW"))
{
fz_obj *obj = fz_dict_gets(p, "Predictor");
if (fz_to_int(obj) > 1)
return fz_open_predict(fz_open_lzwd(chain, p), p);
return fz_open_lzwd(chain, p);
}
else if (!strcmp(s, "JBIG2Decode"))
{
fz_obj *obj = fz_dict_gets(p, "JBIG2Globals");
if (obj)
{
fz_buffer *globals;
error = pdf_load_stream(&globals, xref, fz_to_num(obj), fz_to_gen(obj));
if (error)
fz_catch(error, "cannot load jbig2 global segments");
chain = fz_open_jbig2d(chain, globals);
fz_drop_buffer(globals);
return chain;
}
return fz_open_jbig2d(chain, NULL);
}
else if (!strcmp(s, "JPXDecode"))
return chain; /* JPX decoding is special cased in the image loading code */
else if (!strcmp(s, "Crypt"))
{
fz_obj *name;
if (!xref->crypt)
{
fz_warn("crypt filter in unencrypted document");
return chain;
}
name = fz_dict_gets(p, "Name");
if (fz_is_name(name))
return pdf_open_crypt_with_filter(chain, xref->crypt, fz_to_name(name), num, gen);
return chain;
}
fz_warn("unknown filter name (%s)", s);
return chain;
}