libcamera  v0.0.0+3695-a2c715d8
Supporting cameras in Linux since 2019
af.h
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1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 /*
3  * Copyright (C) 2021, Red Hat
4  *
5  * af.h - IPU3 Af algorithm
6  */
7 
8 #pragma once
9 
10 #include <linux/intel-ipu3.h>
11 
12 #include <libcamera/base/utils.h>
13 
14 #include <libcamera/geometry.h>
15 
16 #include "algorithm.h"
17 
18 namespace libcamera {
19 
20 namespace ipa::ipu3::algorithms {
21 
22 class Af : public Algorithm
23 {
24  /* The format of y_table. From ipu3-ipa repo */
25  typedef struct __attribute__((packed)) y_table_item {
26  uint16_t y1_avg;
27  uint16_t y2_avg;
28  } y_table_item_t;
29 public:
30  Af();
31  ~Af() = default;
32 
33  void prepare(IPAContext &context, ipu3_uapi_params *params) override;
34  int configure(IPAContext &context, const IPAConfigInfo &configInfo) override;
35  void process(IPAContext &context, IPAFrameContext *frameContext,
36  const ipu3_uapi_stats_3a *stats) override;
37 
38 private:
39  void afCoarseScan(IPAContext &context);
40  void afFineScan(IPAContext &context);
41  bool afScan(IPAContext &context, int min_step);
42  void afReset(IPAContext &context);
43  bool afNeedIgnoreFrame();
44  void afIgnoreFrameReset();
45  double afEstimateVariance(Span<const y_table_item_t> y_items, bool isY1);
46 
47  bool afIsOutOfFocus(IPAContext context);
48 
49  /* VCM step configuration. It is the current setting of the VCM step. */
50  uint32_t focus_;
51  /* The best VCM step. It is a local optimum VCM step during scanning. */
52  uint32_t bestFocus_;
53  /* Current AF statistic variance. */
54  double currentVariance_;
55  /* The frames are ignore before starting measuring. */
56  uint32_t ignoreCounter_;
57  /* It is used to determine the derivative during scanning */
58  double previousVariance_;
59  /* The designated maximum range of focus scanning. */
60  uint32_t maxStep_;
61  /* If the coarse scan completes, it is set to true. */
62  bool coarseCompleted_;
63  /* If the fine scan completes, it is set to true. */
64  bool fineCompleted_;
65 };
66 
67 } /* namespace ipa::ipu3::algorithms */
68 
69 } /* namespace libcamera */
Global IPA context data shared between all algorithms.
Definition: ipa_context.h:92
Top-level libcamera namespace.
Definition: backtrace.h:17
int configure(IPAContext &context, const IPAConfigInfo &configInfo) override
Configure the Af given a configInfo.
Definition: af.cpp:135
Miscellaneous utility functions.
void process(IPAContext &context, IPAFrameContext *frameContext, const ipu3_uapi_stats_3a *stats) override
Determine the max contrast image and lens position.
Definition: af.cpp:423
An auto-focus algorithm based on IPU3 statistics.
Definition: af.h:22
void prepare(IPAContext &context, ipu3_uapi_params *params) override
Fill the params buffer with ISP processing parameters for a frame.
Definition: af.cpp:119
Context for a frame.
Definition: ipa_context.h:79
The base class for all IPA algorithms.
Definition: algorithm.h:19
Data structures related to geometric objects.