dotmax 0.1.7

High-performance terminal braille rendering for images, animations, and graphics
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
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272

//! Integration tests for temporal coherence algorithms.
//!
//! These tests verify that the temporal coherence module reduces flicker
//! when processing sequences of frames.

use dotmax::image::temporal::{
    average_flicker, measure_flicker, FrameBlender, HysteresisFilter, TemporalCoherence,
    TemporalConfig,
};
use image::GrayImage;

// ============================================================================
// Flicker Measurement Tests
// ============================================================================

#[test]
fn test_measure_flicker_identical_frames() {
    let frame = vec![true, false, true, false, true];
    let flicker = measure_flicker(&frame, &frame);
    assert!((flicker - 0.0).abs() < f64::EPSILON, "Identical frames should have 0 flicker");
}

#[test]
fn test_measure_flicker_completely_different() {
    let frame1 = vec![true, true, true, true];
    let frame2 = vec![false, false, false, false];
    let flicker = measure_flicker(&frame1, &frame2);
    assert!((flicker - 1.0).abs() < f64::EPSILON, "Opposite frames should have 100% flicker");
}

#[test]
fn test_measure_flicker_partial_change() {
    let frame1 = vec![true, false, true, false];
    let frame2 = vec![true, true, true, false]; // 1 change out of 4
    let flicker = measure_flicker(&frame1, &frame2);
    assert!((flicker - 0.25).abs() < 0.001, "25% of dots changed");
}

#[test]
fn test_average_flicker_calculation() {
    let frames = vec![
        vec![true, false, true, false], // frame 0
        vec![true, true, true, false],  // 1 change from frame 0 (25%)
        vec![false, true, false, false], // 2 changes from frame 1 (50%)
    ];
    let avg = average_flicker(&frames);
    // (0.25 + 0.50) / 2 = 0.375
    assert!((avg - 0.375).abs() < 0.001, "Average should be 37.5%");
}

#[test]
fn test_average_flicker_single_frame() {
    let frames = vec![vec![true, false]];
    let avg = average_flicker(&frames);
    assert!((avg - 0.0).abs() < f64::EPSILON, "Single frame should have 0 average flicker");
}

#[test]
fn test_average_flicker_empty() {
    let frames: Vec<Vec<bool>> = vec![];
    let avg = average_flicker(&frames);
    assert!((avg - 0.0).abs() < f64::EPSILON, "Empty frames should have 0 flicker");
}

// ============================================================================
// Hysteresis Filter Tests
// ============================================================================

#[test]
fn test_hysteresis_reduces_noise_flicker() {
    // Simulate a sequence of frames where a pixel oscillates near the threshold
    // Without hysteresis, it would flicker rapidly
    let threshold: u8 = 128;
    let margin: u8 = 15;

    let mut filter = HysteresisFilter::new(margin);

    // Frame 1: Pixel at 130 (above threshold) -> ON
    let frame1 = GrayImage::from_fn(1, 1, |_, _| image::Luma([130]));
    let result1 = filter.apply(&frame1, threshold);
    assert_eq!(result1.get_pixel(0, 0).0[0], 255, "Should be ON");

    // Frame 2: Pixel drops to 120 (below threshold but above low_thresh=113)
    // With hysteresis, should stay ON
    let frame2 = GrayImage::from_fn(1, 1, |_, _| image::Luma([120]));
    let result2 = filter.apply(&frame2, threshold);
    assert_eq!(result2.get_pixel(0, 0).0[0], 255, "Should stay ON (hysteresis)");

    // Frame 3: Pixel drops to 110 (below low_thresh=113)
    // Now it should turn OFF
    let frame3 = GrayImage::from_fn(1, 1, |_, _| image::Luma([110]));
    let result3 = filter.apply(&frame3, threshold);
    assert_eq!(result3.get_pixel(0, 0).0[0], 0, "Should turn OFF");

    // Frame 4: Pixel rises to 130 (below high_thresh=143 but above threshold)
    // With hysteresis, should stay OFF
    let frame4 = GrayImage::from_fn(1, 1, |_, _| image::Luma([130]));
    let result4 = filter.apply(&frame4, threshold);
    assert_eq!(result4.get_pixel(0, 0).0[0], 0, "Should stay OFF (hysteresis)");

    // Frame 5: Pixel rises to 150 (above high_thresh=143)
    // Now it should turn ON
    let frame5 = GrayImage::from_fn(1, 1, |_, _| image::Luma([150]));
    let result5 = filter.apply(&frame5, threshold);
    assert_eq!(result5.get_pixel(0, 0).0[0], 255, "Should turn ON");
}

#[test]
fn test_hysteresis_dimension_change_resets() {
    let mut filter = HysteresisFilter::new(10);

    // Apply to 2x2 frame
    let frame1 = GrayImage::from_fn(2, 2, |_, _| image::Luma([150]));
    let _ = filter.apply(&frame1, 128);

    // Apply to 3x3 frame (dimension change)
    let frame2 = GrayImage::from_fn(3, 3, |_, _| image::Luma([100]));
    let result = filter.apply(&frame2, 128);

    // First frame after resize should use standard threshold
    assert_eq!(result.get_pixel(0, 0).0[0], 0, "100 < 128, should be OFF");
}

// ============================================================================
// Frame Blender Tests
// ============================================================================

#[test]
fn test_frame_blender_smooths_transitions() {
    let mut blender = FrameBlender::new(0.5);

    // Frame 1: All 100
    let frame1 = GrayImage::from_fn(2, 2, |_, _| image::Luma([100]));
    let result1 = blender.blend(&frame1);
    assert_eq!(result1.get_pixel(0, 0).0[0], 100, "First frame unchanged");

    // Frame 2: All 200
    // With alpha=0.5: output = 0.5*200 + 0.5*100 = 150
    let frame2 = GrayImage::from_fn(2, 2, |_, _| image::Luma([200]));
    let result2 = blender.blend(&frame2);
    assert_eq!(result2.get_pixel(0, 0).0[0], 150, "Blended to 150");

    // Frame 3: All 200 again
    // output = 0.5*200 + 0.5*150 = 175
    let frame3 = GrayImage::from_fn(2, 2, |_, _| image::Luma([200]));
    let result3 = blender.blend(&frame3);
    assert_eq!(result3.get_pixel(0, 0).0[0], 175, "Converging to 200");
}

#[test]
fn test_frame_blender_alpha_1_passes_through() {
    let mut blender = FrameBlender::new(1.0);

    let frame1 = GrayImage::from_fn(2, 2, |_, _| image::Luma([100]));
    let _ = blender.blend(&frame1);

    let frame2 = GrayImage::from_fn(2, 2, |_, _| image::Luma([200]));
    let result = blender.blend(&frame2);

    // With alpha=1.0, should be exactly frame2
    assert_eq!(result.get_pixel(0, 0).0[0], 200);
}

// ============================================================================
// Temporal Coherence Integration Tests
// ============================================================================

#[test]
fn test_temporal_config_presets() {
    let default = TemporalConfig::default();
    assert!(default.hysteresis_enabled);
    assert!(!default.frame_blend_enabled);
    assert!(!default.dot_filter_enabled);

    let video = TemporalConfig::video();
    assert!(video.hysteresis_enabled);
    assert!(video.frame_blend_enabled);

    let webcam = TemporalConfig::webcam();
    assert!(webcam.hysteresis_enabled);
    assert!(webcam.frame_blend_enabled);
    assert!(webcam.dot_filter_enabled);

    let disabled = TemporalConfig::disabled();
    assert!(!disabled.hysteresis_enabled);
    assert!(!disabled.frame_blend_enabled);
    assert!(!disabled.dot_filter_enabled);
}

#[test]
fn test_temporal_coherence_reduces_flicker() {
    // Create frames that would cause flicker without temporal coherence
    // Pixels alternate between 125 and 130 around threshold 128
    let threshold = 128u8;

    // Without temporal coherence: every frame would flip
    let frames_raw: Vec<GrayImage> = (0..10)
        .map(|i| {
            let value = if i % 2 == 0 { 125 } else { 130 };
            GrayImage::from_fn(10, 10, |_, _| image::Luma([value]))
        })
        .collect();

    // Process without temporal coherence (simple threshold)
    let results_without: Vec<Vec<bool>> = frames_raw
        .iter()
        .map(|frame| {
            frame
                .pixels()
                .map(|p| p.0[0] >= threshold)
                .collect()
        })
        .collect();

    let flicker_without = average_flicker(&results_without);

    // Process with temporal coherence
    let mut coherence = TemporalCoherence::new(TemporalConfig::default());
    let results_with: Vec<Vec<bool>> = frames_raw
        .iter()
        .map(|frame| {
            let binary = coherence.process_grayscale(frame, threshold);
            binary.pixels().map(|p| p.0[0] > 0).collect()
        })
        .collect();

    let flicker_with = average_flicker(&results_with);

    // Temporal coherence should reduce flicker
    assert!(
        flicker_with < flicker_without,
        "Temporal coherence should reduce flicker: without={:.2}%, with={:.2}%",
        flicker_without * 100.0,
        flicker_with * 100.0
    );
}

#[test]
fn test_temporal_coherence_reset() {
    let mut coherence = TemporalCoherence::new(TemporalConfig::video());

    // Process some frames
    let frame = GrayImage::from_fn(10, 10, |_, _| image::Luma([150]));
    let _ = coherence.process_grayscale(&frame, 128);
    let _ = coherence.process_grayscale(&frame, 128);

    // Reset
    coherence.reset();

    // Next frame should be treated as first frame
    let frame2 = GrayImage::from_fn(10, 10, |_, _| image::Luma([100]));
    let result = coherence.process_grayscale(&frame2, 128);

    // 100 < 128, so should be OFF
    assert_eq!(result.get_pixel(0, 0).0[0], 0, "After reset, should use standard threshold");
}

#[test]
fn test_temporal_coherence_config_update() {
    let mut coherence = TemporalCoherence::new(TemporalConfig::default());

    // Verify initial config
    assert!(coherence.config().hysteresis_enabled);
    assert!(!coherence.config().frame_blend_enabled);

    // Update config
    coherence.set_config(TemporalConfig::video());

    // Verify updated config
    assert!(coherence.config().hysteresis_enabled);
    assert!(coherence.config().frame_blend_enabled);
}