/*!
* \brief readHeaderJpeg()
*
* \param[in] filename
* \param[out] pw [optional]
* [out] ph ([optional]
* [out] pspp ([optional] samples/pixel
* \param[out] pycck [optional] 1 if ycck color space; 0 otherwise
* \param[out] pcmyk [optional] 1 if cmyk color space; 0 otherwise
* \return 0 if OK, 1 on error
*/
l_int32
readHeaderJpeg(const char *filename,
l_int32 *pw,
l_int32 *ph,
l_int32 *pspp,
l_int32 *pycck,
l_int32 *pcmyk)
{
l_int32 ret;
FILE *fp;
PROCNAME("readHeaderJpeg");
if (pw) *pw = 0;
if (ph) *ph = 0;
if (pspp) *pspp = 0;
if (pycck) *pycck = 0;
if (pcmyk) *pcmyk = 0;
if (!filename)
return ERROR_INT("filename not defined", procName, 1);
if (!pw && !ph && !pspp && !pycck && !pcmyk)
return ERROR_INT("no results requested", procName, 1);
if ((fp = fopenReadStream(filename)) == NULL)
return ERROR_INT("image file not found", procName, 1);
ret = freadHeaderJpeg(fp, pw, ph, pspp, pycck, pcmyk);
fclose(fp);
return ret;
}
/*!
* \brief readHeaderMemJpeg()
*
* \param[in] data const; jpeg-encoded
* \param[in] size of data
* \param[out] pw [optional]
* [out] ph ([optional]
* [out] pspp ([optional] samples/pixel
* \param[out] pycck [optional] 1 if ycck color space; 0 otherwise
* \param[out] pcmyk [optional] 1 if cmyk color space; 0 otherwise
* \return 0 if OK, 1 on error
*/
l_int32
readHeaderMemJpeg(const l_uint8 *data,
size_t size,
l_int32 *pw,
l_int32 *ph,
l_int32 *pspp,
l_int32 *pycck,
l_int32 *pcmyk)
{
l_int32 ret;
FILE *fp;
PROCNAME("readHeaderMemJpeg");
if (pw) *pw = 0;
if (ph) *ph = 0;
if (pspp) *pspp = 0;
if (pycck) *pycck = 0;
if (pcmyk) *pcmyk = 0;
if (!data)
return ERROR_INT("data not defined", procName, 1);
if (!pw && !ph && !pspp && !pycck && !pcmyk)
return ERROR_INT("no results requested", procName, 1);
if ((fp = fopenReadFromMemory(data, size)) == NULL)
return ERROR_INT("stream not opened", procName, 1);
ret = freadHeaderJpeg(fp, pw, ph, pspp, pycck, pcmyk);
fclose(fp);
return ret;
}
/*!
* readHeaderMemJpeg()
*
* Input: data (const; jpeg-encoded)
* size (of data)
* &w (<optional return>)
* &h (<optional return>)
* &spp (<optional return>, samples/pixel)
* &ycck (<optional return>, 1 if ycck color space; 0 otherwise)
* &cmyk (<optional return>, 1 if cmyk color space; 0 otherwise)
* Return: 0 if OK, 1 on error
*/
l_int32
readHeaderMemJpeg(const l_uint8 *data,
size_t size,
l_int32 *pw,
l_int32 *ph,
l_int32 *pspp,
l_int32 *pycck,
l_int32 *pcmyk)
{
l_int32 ret;
FILE *fp;
PROCNAME("readHeaderMemJpeg");
if (pw) *pw = 0;
if (ph) *ph = 0;
if (pspp) *pspp = 0;
if (pycck) *pycck = 0;
if (pcmyk) *pcmyk = 0;
if (!data)
return ERROR_INT("data not defined", procName, 1);
if (!pw && !ph && !pspp && !pycck && !pcmyk)
return ERROR_INT("no results requested", procName, 1);
#if HAVE_FMEMOPEN
if ((fp = fmemopen((l_uint8 *)data, size, "r")) == NULL)
return ERROR_INT("stream not opened", procName, 1);
#else
L_WARNING("work-around: writing to a temp file\n", procName);
if ((fp = tmpfile()) == NULL)
return ERROR_INT("tmpfile stream not opened", procName, 1);
fwrite(data, 1, size, fp);
rewind(fp);
#endif /* HAVE_FMEMOPEN */
ret = freadHeaderJpeg(fp, pw, ph, pspp, pycck, pcmyk);
fclose(fp);
return ret;
}
// TODO(jbreiden) I hear that you can pull the flate stream out
// of a PNG file and, by mentioning the predictor in the PDF object,
// make most of them work without transcoding. If so that's a big win
// versus what we do now. Try it out.
bool TessPDFRenderer::fileToPDFObj(char *filename, long int objnum,
char **pdf_object,
long int *pdf_object_size) {
char b1[kBasicBufSize];
char b2[kBasicBufSize];
if (!pdf_object_size || !pdf_object)
return false;
*pdf_object = NULL;
*pdf_object_size = 0;
if (!filename)
return false;
FILE *fp = fopen(filename, "rb");
if (!fp)
return false;
int format;
findFileFormatStream(fp, &format);
if (format != IFF_JFIF_JPEG) {
fclose(fp);
return false;
}
fseek(fp, 0, SEEK_END);
long int jpeg_size = ftell(fp);
fseek(fp, 0, SEEK_SET);
int spp, cmyk, w, h;
freadHeaderJpeg(fp, &w, &h, &spp, NULL, &cmyk);
const char *colorspace;
switch (spp) {
case 1:
colorspace = "/DeviceGray";
break;
case 3:
colorspace = "/DeviceRGB";
break;
case 4:
if (cmyk)
colorspace = "/DeviceCMYK";
else
return false;
break;
default:
return false;
}
// IMAGE
snprintf(b1, sizeof(b1),
"%ld 0 obj\n"
"<<\n"
" /Length %ld\n"
" /Subtype /Image\n"
" /ColorSpace %s\n"
" /Width %d\n"
" /Height %d\n"
" /BitsPerComponent 8\n"
" /Filter /DCTDecode\n"
">>\n"
"stream\n", objnum, jpeg_size,
colorspace, w, h);
size_t b1_len = strlen(b1);
snprintf(b2, sizeof(b2),
"\n"
"endstream\n"
"endobj\n");
size_t b2_len = strlen(b2);
*pdf_object_size = b1_len + jpeg_size + b2_len;
*pdf_object = new char[*pdf_object_size];
if (!pdf_object)
return false;
memcpy(*pdf_object, b1, b1_len);
if (static_cast<int>(fread(*pdf_object + b1_len, 1, jpeg_size, fp)) !=
jpeg_size) {
delete[] pdf_object;
return false;
}
memcpy(*pdf_object + b1_len + jpeg_size, b2, b2_len);
fclose(fp);
return true;
}
