#include <string.h>
#include "allheaders.h"

Functions
PIXA *	pixaReadFiles (const char dirname, const char substr)

PIXA *	pixaReadFilesSA (SARRAY *sa)

PIX *	pixRead (const char *filename)

PIX *	pixReadWithHint (const char *filename, l_int32 hint)

PIX *	pixReadIndexed (SARRAY *sa, l_int32 index)

PIX *	pixReadStream (FILE *fp, l_int32 hint)

l_ok	pixReadHeader (const char filename, l_int32 pformat, l_int32 pw, l_int32 ph, l_int32 pbps, l_int32 pspp, l_int32 *piscmap)

l_ok	findFileFormat (const char filename, l_int32 pformat)

l_ok	findFileFormatStream (FILE fp, l_int32 pformat)

l_ok	findFileFormatBuffer (const l_uint8 buf, l_int32 pformat)

l_int32	fileFormatIsTiff (FILE *fp)

PIX *	pixReadMem (const l_uint8 *data, size_t size)

l_ok	pixReadHeaderMem (const l_uint8 data, size_t size, l_int32 pformat, l_int32 pw, l_int32 ph, l_int32 pbps, l_int32 pspp, l_int32 *piscmap)

l_ok	writeImageFileInfo (const char filename, FILE fpout, l_int32 headeronly)

l_ok	ioFormatTest (const char *filename)

Variables
static const char *	FILE_BMP = "/tmp/lept/format/file.bmp"

static const char *	FILE_PNG = "/tmp/lept/format/file.png"

static const char *	FILE_PNM = "/tmp/lept/format/file.pnm"

static const char *	FILE_G3 = "/tmp/lept/format/file_g3.tif"

static const char *	FILE_G4 = "/tmp/lept/format/file_g4.tif"

static const char *	FILE_RLE = "/tmp/lept/format/file_rle.tif"

static const char *	FILE_PB = "/tmp/lept/format/file_packbits.tif"

static const char *	FILE_LZW = "/tmp/lept/format/file_lzw.tif"

static const char *	FILE_ZIP = "/tmp/lept/format/file_zip.tif"

static const char *	FILE_TIFF_JPEG = "/tmp/lept/format/file_jpeg.tif"

static const char *	FILE_TIFF = "/tmp/lept/format/file.tif"

static const char *	FILE_JPG = "/tmp/lept/format/file.jpg"

static const char *	FILE_GIF = "/tmp/lept/format/file.gif"

static const char *	FILE_WEBP = "/tmp/lept/format/file.webp"

static const char *	FILE_JP2K = "/tmp/lept/format/file.jp2"

static const unsigned char	JP2K_CODESTREAM [4] = { 0xff, 0x4f, 0xff, 0x51 }

static const unsigned char	JP2K_IMAGE_DATA [12]

const char *	ImageFileFormatExtensions []

Detailed Description

: reads image on file into memory


     Top-level functions for reading images from file
          PIXA      *pixaReadFiles()
          PIXA      *pixaReadFilesSA()
          PIX       *pixRead()
          PIX       *pixReadWithHint()
          PIX       *pixReadIndexed()
          PIX       *pixReadStream()

     Read header information from file
          l_int32    pixReadHeader()

     Format finders
          l_int32    findFileFormat()
          l_int32    findFileFormatStream()
          l_int32    findFileFormatBuffer()
          l_int32    fileFormatIsTiff()

     Read from memory
          PIX       *pixReadMem()
          l_int32    pixReadHeaderMem()

     Output image file information
          void       writeImageFileInfo()

     Test function for I/O with different formats
          l_int32    ioFormatTest()

 Supported file formats:
 (1) Reading is supported without any external libraries:
         bmp
         pnm   (including pbm, pgm, etc)
         spix  (raw serialized)
 (2) Reading is supported with installation of external libraries:
         png
         jpg   (standard jfif version)
         tiff  (including most varieties of compression)
         gif
         webp
         jp2 (jpeg 2000)
 (3) Other file types will get an "unknown format" error.

Definition in file readfile.c.

Function Documentation

◆ fileFormatIsTiff()

l_int32 fileFormatIsTiff ( FILE * fp )

fileFormatIsTiff()

Parameters

[in] fp file stream

Returns: 1 if file is tiff; 0 otherwise or on error

Definition at line 780 of file readfile.c.

References findFileFormatStream().

◆ findFileFormat()

l_ok findFileFormat	(	const char *	filename,
		l_int32 *	pformat )

findFileFormat()

Parameters

[in]	filename
[out]	pformat	found format

Returns: 0 if OK, 1 on error or if format is not recognized

Definition at line 570 of file readfile.c.

References findFileFormatStream().

Referenced by writeImageFileInfo().

◆ findFileFormatBuffer()

l_ok findFileFormatBuffer	(	const l_uint8 *	buf,
		l_int32 *	pformat )

findFileFormatBuffer()

Parameters

[in]	buf	byte buffer at least 12 bytes in size; we can't check
[out]	pformat	found format

Returns: 0 if OK, 1 on error or if format is not recognized

Notes:
     (1) This determines the file format from the first 12 bytes in
         the compressed data stream, which are stored in memory.
     (2) For tiff files, this returns IFF_TIFF.  The specific tiff
         compression is then determined using findTiffCompression().

Definition at line 653 of file readfile.c.

References BMP_ID, TIFF_BIGEND_ID, and TIFF_LITTLEEND_ID.

Referenced by findFileFormatStream(), pixReadHeaderMem(), and pixReadMem().

◆ findFileFormatStream()

l_ok findFileFormatStream	(	FILE *	fp,
		l_int32 *	pformat )

findFileFormatStream()

Parameters

[in]	fp	file stream
[out]	pformat	found format

Returns: 0 if OK, 1 on error or if format is not recognized

Notes:
     (1) Important: Side effect -- this resets fp to BOF.

Definition at line 603 of file readfile.c.

References findFileFormatBuffer().

Referenced by fileFormatIsTiff(), findFileFormat(), pixReadHeader(), and pixReadStream().

◆ ioFormatTest()

l_ok ioFormatTest ( const char * filename )

ioFormatTest()

Parameters

[in] filename input image file

Returns: 0 if OK; 1 on error or if the test fails

Notes:
     (1) This writes and reads a set of output files losslessly
         in different formats to /tmp/format/, and tests that the
         result before and after is unchanged.
     (2) This should work properly on input images of any depth,
         with and without colormaps.
     (3) All supported formats are tested for bmp, png, tiff and
         non-ascii pnm.  Ascii pnm also works (but who'd ever want
         to use it?)   We allow 2 bpp bmp, although it's not
         supported elsewhere.  And we don't support reading
         16 bpp png, although this can be turned on in pngio.c.
     (4) This silently skips png or tiff testing if HAVE_LIBPNG
         or HAVE_LIBTIFF are 0, respectively.

Definition at line 1261 of file readfile.c.

References pixRead(), and REMOVE_CMAP_BASED_ON_SRC.

◆ pixaReadFiles()

PIXA * pixaReadFiles	(	const char *	dirname,
		const char *	substr )

pixaReadFiles()

Parameters

[in]	dirname
[in]	substr	[optional] substring filter on filenames; can be null

Returns: pixa, or NULL on error

Notes:
     (1) dirname is the full path for the directory.
     (2) substr is the part of the file name (excluding
         the directory) that is to be matched.  All matching
         filenames are read into the Pixa.  If substr is NULL,
         all filenames are read into the Pixa.

Definition at line 127 of file readfile.c.

References pixaReadFilesSA().

◆ pixaReadFilesSA()

PIXA * pixaReadFilesSA ( SARRAY * sa )

pixaReadFilesSA()

Parameters

[in] sa full pathnames for all files

Returns: pixa, or NULL on error

Definition at line 152 of file readfile.c.

References L_INSERT, L_NOCOPY, and pixRead().

Referenced by pixaReadFiles().

◆ pixRead()

PIX * pixRead ( const char * filename )

pixRead()

Parameters

[in] filename with full pathname or in local directory

Returns: pix if OK; NULL on error

Notes:
     (1) See at top of file for supported formats.

Definition at line 189 of file readfile.c.

References pixReadStream().

Referenced by ioFormatTest(), pixaReadFilesSA(), pixReadHeader(), pixReadIndexed(), and writeImageFileInfo().

◆ pixReadHeader()

l_ok pixReadHeader	(	const char *	filename,
		l_int32 *	pformat,
		l_int32 *	pw,
		l_int32 *	ph,
		l_int32 *	pbps,
		l_int32 *	pspp,
		l_int32 *	piscmap )

pixReadHeader()

Parameters

[in]	filename	with full pathname or in local directory
[out]	pformat	[optional] file format
[out]	pw,ph	[optional] width and height
[out]	pbps	[optional] bits/sample
[out]	pspp	[optional] samples/pixel 1, 3 or 4
[out]	piscmap	[optional] 1 if cmap exists; 0 otherwise

Returns: 0 if OK, 1 on error

Notes:
     (1) This reads the actual headers for jpeg, png, tiff and pnm.
         For bmp and gif, we cheat and read the entire file into a pix,
         from which we extract the "header" information.

Definition at line 434 of file readfile.c.

References findFileFormatStream(), and pixRead().

Referenced by writeImageFileInfo().

◆ pixReadHeaderMem()

l_ok pixReadHeaderMem	(	const l_uint8 *	data,
		size_t	size,
		l_int32 *	pformat,
		l_int32 *	pw,
		l_int32 *	ph,
		l_int32 *	pbps,
		l_int32 *	pspp,
		l_int32 *	piscmap )

pixReadHeaderMem()

Parameters

[in]	data	const; encoded
[in]	size	size of data
[out]	pformat	[optional] image format
[out]	pw,ph	[optional] width and height
[out]	pbps	[optional] bits/sample
[out]	pspp	[optional] samples/pixel 1, 3 or 4
[out]	piscmap	[optional] 1 if cmap exists; 0 otherwise

Returns: 0 if OK, 1 on error

Notes:
     (1) This reads the actual headers for jpeg, png, tiff, jp2k and pnm.
         For bmp and gif, we cheat and read all the data into a pix,
         from which we extract the "header" information.
     (2) The amount of data required depends on the format.  For
         png, it requires less than 30 bytes, but for jpeg it can
         require most of the compressed file.  In practice, the data
         is typically the entire compressed file in memory.
     (3) findFileFormatBuffer() requires up to 12 bytes to decide on
         the format, which we require.

Definition at line 950 of file readfile.c.

References findFileFormatBuffer().

◆ pixReadIndexed()

PIX * pixReadIndexed	(	SARRAY *	sa,
		l_int32	index )

pixReadIndexed()

Parameters

[in]	sa	string array of full pathnames
[in]	index	into pathname array

Returns: pix if OK; null if not found

Notes:
     (1) This function is useful for selecting image files from a
         directory, where the integer index is embedded into
         the file name.
     (2) This is typically done by generating the sarray using
         getNumberedPathnamesInDirectory(), so that the index
         pathname would have the number index in it.  The size
         of the sarray should be the largest number (plus 1) appearing
         in the file names, respecting the constraints in the
         call to getNumberedPathnamesInDirectory().
     (3) Consequently, for some indices into the sarray, there may
         be no pathnames in the directory containing that number.
         By convention, we place empty C strings ("") in those
         locations in the sarray, and it is not an error if such
         a string is encountered and no pix is returned.
         Therefore, the caller must verify that a pix is returned.
     (4) See convertSegmentedPagesToPS() in src/psio1.c for an
         example of usage.

Definition at line 273 of file readfile.c.

References L_NOCOPY, and pixRead().

◆ pixReadMem()

PIX * pixReadMem	(	const l_uint8 *	data,
		size_t	size )

pixReadMem()

Parameters

[in]	data	const; encoded
[in]	size	size of data

Returns: pix, or NULL on error

Notes:
     (1) This is a variation of pixReadStream(), where the data is read
         from a memory buffer rather than a file.
     (2) On Windows, this only reads tiff formatted files directly from
         memory.  For other formats, it writes to a temp file and
         decompresses from file.
     (3) findFileFormatBuffer() requires up to 12 bytes to decide on
         the format.  That determines the constraint here.  But in
         fact the data must contain the entire compressed string for
         the image.

Definition at line 822 of file readfile.c.

References findFileFormatBuffer().

◆ pixReadStream()

PIX * pixReadStream	(	FILE *	fp,
		l_int32	hint )

pixReadStream()

Parameters

[in]	fp	file stream
[in]	hint	bitwise OR of L_HINT_* values for jpeg; 0 for no hint

Returns: pix if OK; NULL on error

Notes:
     (1) The hint only applies to jpeg.

Definition at line 312 of file readfile.c.

References findFileFormatStream().

Referenced by pixRead(), and pixReadWithHint().

◆ pixReadWithHint()

PIX * pixReadWithHint	(	const char *	filename,
		l_int32	hint )

pixReadWithHint()

Parameters

[in]	filename	with full pathname or in local directory
[in]	hint	bitwise OR of L_HINT_* values for jpeg; use 0 for no hint

Returns: pix if OK; NULL on error

Notes:
     (1) The hint is not binding, but may be used to optimize jpeg decoding.
         Use 0 for no hinting.

Definition at line 224 of file readfile.c.

References pixReadStream().

◆ writeImageFileInfo()

l_ok writeImageFileInfo	(	const char *	filename,
		FILE *	fpout,
		l_int32	headeronly )

writeImageFileInfo()

Parameters

[in]	filename	input file
[in]	fpout	output file stream
[in]	headeronly	1 to read only the header; 0 to read both the header and the input file

Returns: 0 if OK; 1 on error

Notes:
     (1) If headeronly == 0 and the image has spp == 4,this will
         also call pixDisplayLayersRGBA() to display the image
         in three views.
     (2) This is a debug function that changes the value of
         var_PNG_STRIP_16_TO_8 to 1 (the default).

Definition at line 1095 of file readfile.c.

References findFileFormat(), pixRead(), and pixReadHeader().

Variable Documentation

◆ FILE_BMP

const char* FILE_BMP = "/tmp/lept/format/file.bmp"

static

Definition at line 82 of file readfile.c.

◆ FILE_G3

const char* FILE_G3 = "/tmp/lept/format/file_g3.tif"

static

Definition at line 85 of file readfile.c.

◆ FILE_G4

const char* FILE_G4 = "/tmp/lept/format/file_g4.tif"

static

Definition at line 86 of file readfile.c.

◆ FILE_GIF

const char* FILE_GIF = "/tmp/lept/format/file.gif"

static

Definition at line 94 of file readfile.c.

◆ FILE_JP2K

const char* FILE_JP2K = "/tmp/lept/format/file.jp2"

static

Definition at line 96 of file readfile.c.

◆ FILE_JPG

const char* FILE_JPG = "/tmp/lept/format/file.jpg"

static

Definition at line 93 of file readfile.c.

◆ FILE_LZW

const char* FILE_LZW = "/tmp/lept/format/file_lzw.tif"

static

Definition at line 89 of file readfile.c.

◆ FILE_PB

const char* FILE_PB = "/tmp/lept/format/file_packbits.tif"

static

Definition at line 88 of file readfile.c.

◆ FILE_PNG

const char* FILE_PNG = "/tmp/lept/format/file.png"

static

Definition at line 83 of file readfile.c.

◆ FILE_PNM

const char* FILE_PNM = "/tmp/lept/format/file.pnm"

static

Definition at line 84 of file readfile.c.

◆ FILE_RLE

const char* FILE_RLE = "/tmp/lept/format/file_rle.tif"

static

Definition at line 87 of file readfile.c.

◆ FILE_TIFF

const char* FILE_TIFF = "/tmp/lept/format/file.tif"

static

Definition at line 92 of file readfile.c.

◆ FILE_TIFF_JPEG

const char* FILE_TIFF_JPEG = "/tmp/lept/format/file_jpeg.tif"

static

Definition at line 91 of file readfile.c.

◆ FILE_WEBP

const char* FILE_WEBP = "/tmp/lept/format/file.webp"

static

Definition at line 95 of file readfile.c.

◆ FILE_ZIP

const char* FILE_ZIP = "/tmp/lept/format/file_zip.tif"

static

Definition at line 90 of file readfile.c.

◆ ImageFileFormatExtensions

const char* ImageFileFormatExtensions[]

extern

Definition at line 122 of file writefile.c.

◆ JP2K_CODESTREAM

const unsigned char JP2K_CODESTREAM[4] = { 0xff, 0x4f, 0xff, 0x51 }

static

Definition at line 101 of file readfile.c.

◆ JP2K_IMAGE_DATA

const unsigned char JP2K_IMAGE_DATA[12]

static

Initial value:

= { 0x00, 0x00, 0x00, 0x0c,
                                                   0x6a, 0x50, 0x20, 0x20,
                                                   0x0d, 0x0a, 0x87, 0x0a }

Definition at line 102 of file readfile.c.

Functions

Variables

Detailed Description

Function Documentation

◆ fileFormatIsTiff()

◆ findFileFormat()

◆ findFileFormatBuffer()

◆ findFileFormatStream()

◆ ioFormatTest()

◆ pixaReadFiles()

◆ pixaReadFilesSA()

◆ pixRead()

◆ pixReadHeader()

◆ pixReadHeaderMem()

◆ pixReadIndexed()

◆ pixReadMem()

◆ pixReadStream()

◆ pixReadWithHint()

◆ writeImageFileInfo()

Variable Documentation

◆ FILE_BMP

◆ FILE_G3

◆ FILE_G4

◆ FILE_GIF

◆ FILE_JP2K

◆ FILE_JPG

◆ FILE_LZW

◆ FILE_PB

◆ FILE_PNG

◆ FILE_PNM

◆ FILE_RLE

◆ FILE_TIFF

◆ FILE_TIFF_JPEG

◆ FILE_WEBP

◆ FILE_ZIP

◆ ImageFileFormatExtensions

◆ JP2K_CODESTREAM

◆ JP2K_IMAGE_DATA