Decode a frame from a file on the filesystem
Synopsis:
#include <img/img.h>
int img_load_file( img_lib_t ilib,
const char* path,
const img_decode_callouts_t* callouts,
img_t* img );
Arguments:
-
ilib
- A handle for the image library, returned by
img_lib_attach()
.
-
path
- The full path to the file from which the data can be read.
-
callouts
- A pointer to an
img_decode_callouts_t
structure that provides system callouts for the decoder. If you specify NULL for this value, a set of default callouts is supplied.
-
img
- The address of an
img_t
structure the function fills in with information about the decoded frame.
You can override elements, such as the format, before the
call to img_load_file():
img.format = IMG_FMT_G8;
img.flags |= IMG_FORMAT;
img_load_file(...);
In the above example, because the format is set before the load
occurs, the libimg forces the loaded image
into IMG_FMT_G8 format, regardless of the actual
source image format.
Library:
libimg
Use the -l img option to
qcc
to link against this library.
Description:
This function decodes a frame from a file on the filesystem. This function decodes only the first frame encountered.
If you want to resize a file when it's loaded, use
img_load_resize_file()
.
Returns:
-
IMG_ERR_OK
- Success
-
IMG_ERR_CORRUPT
- Invalid data encountered in the file, preventing the decode from proceeding. Some of the frame may be intact.
-
IMG_ERR_DLL
- An error occurred processing the DLL that handles the file type. Check to make sure that the DLL is not missing or corrupt.
-
IMG_ERR_FILE
- Error accessing path (
errno
is set).
-
IMG_ERR_FORMAT
- No appopriate codec could be found. The codec you require could be missing or corrupt, or the file could be corrupt.
-
IMG_ERR_INTR
- Decode was interrupted by application.
-
IMG_ERR_MEM
- Memory-allocation failure.
-
IMG_ERR_NODATA
- No frame data was present. This error is highly unlikely, as files generally contain at least one frame.
-
IMG_ERR_NOSUPPORT
- Output data not supported; the codec and application could not agree on an output format.
-
IMG_ERR_TRUNC
- Premature end of file encountered. Some of the frame may be intact.
Classification:
Image library
| Safety: |
|
| Interrupt handler |
No |
| Signal handler |
No |
| Thread |
No |