mirrors/libfprint
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/libfprint/libfprint.git synced 2025-11-15 07:38:12 +00:00
Code Issues Packages Projects Releases Wiki Activity

Identification infrastructure

Browse Source
This commit is contained in:
Daniel Drake
2007-11-20 21:52:10 +00:00
parent dbcd293ab3
commit 3f70d6f794
3 changed files with 141 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

94
libfprint/core.c
View File

@@ -747,6 +747,18 @@ API_EXPORTED int fp_dev_supports_imaging(struct fp_dev *dev)
return dev->drv->type == DRIVER_IMAGING;
}
/** \ingroup dev
* Determines if a device is capable of \ref identification "identification"
* through fp_identify_finger() and similar. Not all devices support this
* functionality.
* \param dev the fingerprint device
* \returns 1 if the device is capable of identification, 0 otherwise.
*/
API_EXPORTED int fp_dev_supports_identification(struct fp_dev *dev)
{
return dev->drv->identify != NULL;
}
/** \ingroup dev
* Captures an \ref img "image" from a device. The returned image is the raw
* image provided by the device, you may wish to \ref img_std "standardize" it.
@@ -1020,6 +1032,88 @@ API_EXPORTED int fp_verify_finger_img(struct fp_dev *dev,
return r;
}
/** \ingroup dev
* Performs a new scan and attempts to identify the scanned finger against
* a collection of previously enrolled fingerprints.
* If the device is an imaging device, it can also return the image from
* the scan, even when identification fails with a RETRY code. It is legal to
* call this function even on non-imaging devices, just don't expect them to
* provide images.
*
* This function returns codes from #fp_verify_result. The return code
* fp_verify_result#FP_VERIFY_MATCH indicates that the scanned fingerprint
* does appear in the print gallery, and the match_offset output parameter
* will indicate the index into the print gallery array of the matched print.
*
* This function will not necessarily examine the whole print gallery, it
* will return as soon as it finds a matching print.
*
* Not all devices support identification. -ENOTSUP will be returned when
* this is the case.
*
* \param dev the device to perform the scan.
* \param print_gallery NULL-terminated array of pointers to the prints to
* identify against. Each one must have been previously enrolled with a device
* compatible to the device selected to perform the scan.
* \param match_offset output location to store the array index of the matched
* gallery print (if any was found). Only valid if FP_VERIFY_MATCH was
* returned.
* \param img location to store the scan image. accepts NULL for no image
* storage. If an image is returned, it must be freed with fp_img_free() after
* use.
* \return negative code on error, otherwise a code from #fp_verify_result
*/
API_EXPORTED int fp_identify_finger_img(struct fp_dev *dev,
struct fp_print_data **print_gallery, size_t *match_offset,
struct fp_img **img)
{
struct fp_driver *drv = dev->drv;
struct fp_img *_img;
int r;
if (!drv->identify) {
fp_dbg("driver %s has no identify func", drv->name);
return -ENOTSUP;
}
fp_dbg("to be handled by %s", drv->name);
r = drv->identify(dev, print_gallery, match_offset, &_img);
if (r < 0) {
fp_dbg("identify error %d", r);
return r;
}
if (img)
*img = _img;
else
fp_img_free(_img);
switch (r) {
case FP_VERIFY_NO_MATCH:
fp_dbg("result: no match");
break;
case FP_VERIFY_MATCH:
fp_dbg("result: match at offset %zd", match_offset);
break;
case FP_VERIFY_RETRY:
fp_dbg("verify should retry");
break;
case FP_VERIFY_RETRY_TOO_SHORT:
fp_dbg("swipe was too short, verify should retry");
break;
case FP_VERIFY_RETRY_CENTER_FINGER:
fp_dbg("finger was not centered, verify should retry");
break;
case FP_VERIFY_RETRY_REMOVE_FINGER:
fp_dbg("scan failed, remove finger and retry");
break;
default:
fp_err("unrecognised return code %d", r);
return -EINVAL;
}
return r;
}
/** \ingroup core
* Initialise libfprint. This function must be called before you attempt to
* use the library in any way.