av-scenechange 0.14.0

Estimates frames in a video where a scenecut would be ideal
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162

use rust::get_sad_internal;
#[cfg(not(asm_x86_64))]
use rust::*;
#[cfg(asm_x86_64)]
use simd_x86::*;
use v_frame::{pixel::Pixel, plane::Plane};

use super::plane::PlaneRegion;
use crate::cpu::CpuFeatureLevel;

mod rust {
    use v_frame::{
        pixel::{CastFromPrimitive, Pixel},
        plane::Plane,
    };

    use crate::{
        data::plane::{Area, PlaneRegion, Rect},
        CpuFeatureLevel,
    };

    pub(super) fn sad_plane_internal<T: Pixel>(
        src: &Plane<T>,
        dst: &Plane<T>,
        _cpu: CpuFeatureLevel,
    ) -> u64 {
        assert_eq!(src.cfg.width, dst.cfg.width);
        assert_eq!(src.cfg.height, dst.cfg.height);

        src.rows_iter()
            .zip(dst.rows_iter())
            .map(|(src, dst)| {
                src.iter()
                    .zip(dst.iter())
                    .map(|(&p1, &p2)| i32::cast_from(p1).abs_diff(i32::cast_from(p2)))
                    .sum::<u32>() as u64
            })
            .sum()
    }

    pub fn get_sad_internal<T: Pixel>(
        plane_org: &PlaneRegion<'_, T>,
        plane_ref: &PlaneRegion<'_, T>,
        w: usize,
        h: usize,
        _bit_depth: usize,
        _cpu: CpuFeatureLevel,
    ) -> u32 {
        debug_assert!(w <= 128 && h <= 128);
        let plane_org = plane_org.subregion(Area::Rect(Rect {
            x: 0,
            y: 0,
            width: w,
            height: h,
        }));
        let plane_ref = plane_ref.subregion(Area::Rect(Rect {
            x: 0,
            y: 0,
            width: w,
            height: h,
        }));

        plane_org
            .rows_iter()
            .zip(plane_ref.rows_iter())
            .map(|(src, dst)| {
                src.iter()
                    .zip(dst)
                    .map(|(&p1, &p2)| i32::cast_from(p1).abs_diff(i32::cast_from(p2)))
                    .sum::<u32>()
            })
            .sum()
    }
}

#[cfg(asm_x86_64)]
mod simd_x86 {
    use v_frame::{
        pixel::{Pixel, PixelType},
        plane::Plane,
    };

    use crate::CpuFeatureLevel;

    macro_rules! decl_sad_plane_fn {
      ($($f:ident),+) => {
        extern "C" {
          $(
            fn $f(
              src: *const u8, dst: *const u8, stride: libc::size_t,
              width: libc::size_t, rows: libc::size_t
            ) -> u64;
          )*
        }
      };
    }

    decl_sad_plane_fn!(avsc_sad_plane_8bpc_sse2, avsc_sad_plane_8bpc_avx2);

    pub(super) fn sad_plane_internal<T: Pixel>(
        src: &Plane<T>,
        dst: &Plane<T>,
        cpu: CpuFeatureLevel,
    ) -> u64 {
        use std::mem;

        assert_eq!(src.cfg.width, dst.cfg.width);
        assert_eq!(src.cfg.stride, dst.cfg.stride);
        assert_eq!(src.cfg.height, dst.cfg.height);
        assert!(src.cfg.width <= src.cfg.stride);

        match T::type_enum() {
            PixelType::U8 => {
                // helper macro to reduce boilerplate
                macro_rules! call_asm {
                    ($func:ident, $src:expr, $dst:expr, $cpu:expr) => {
                        // SAFETY: Calls Assembly code.
                        unsafe {
                            let result = $func(
                                mem::transmute::<*const T, *const u8>(src.data_origin().as_ptr()),
                                mem::transmute::<*const T, *const u8>(dst.data_origin().as_ptr()),
                                src.cfg.stride,
                                src.cfg.width,
                                src.cfg.height,
                            );

                            result
                        }
                    };
                }

                if cpu >= CpuFeatureLevel::AVX2 {
                    call_asm!(avsc_sad_plane_8bpc_avx2, src, dst, cpu)
                } else if cpu >= CpuFeatureLevel::SSE2 {
                    call_asm!(avsc_sad_plane_8bpc_sse2, src, dst, cpu)
                } else {
                    super::rust::sad_plane_internal(src, dst, cpu)
                }
            }
            PixelType::U16 => super::rust::sad_plane_internal(src, dst, cpu),
        }
    }
}

/// Compute the sum of absolute differences (SADs) on 2 rows of pixels
///
/// This differs from other SAD functions in that it operates over a row
/// (or line) of unknown length rather than a `PlaneRegion<T>`.
pub(crate) fn sad_plane<T: Pixel>(src: &Plane<T>, dst: &Plane<T>, cpu: CpuFeatureLevel) -> u64 {
    sad_plane_internal(src, dst, cpu)
}

pub(crate) fn get_sad<T: Pixel>(
    plane_org: &PlaneRegion<'_, T>,
    plane_ref: &PlaneRegion<'_, T>,
    w: usize,
    h: usize,
    bit_depth: usize,
    cpu: CpuFeatureLevel,
) -> u32 {
    get_sad_internal(plane_org, plane_ref, w, h, bit_depth, cpu)
}