tests: add generated image tests

This commit is contained in:
Ivan Smirnov 2022-01-05 17:17:42 +03:00
parent 8c7b78a97f
commit c2d23f8dec
2 changed files with 174 additions and 0 deletions

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@ -33,6 +33,8 @@ anyhow = "1.0"
png = "0.17" png = "0.17"
walkdir = "2.3" walkdir = "2.3"
cfg-if = "1.0" cfg-if = "1.0"
rand = "0.8"
libqoi = { path = "libqoi"}
[lib] [lib]
name = "qoi_fast" name = "qoi_fast"

172
tests/test_gen.rs Normal file
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@ -0,0 +1,172 @@
mod common;
use cfg_if::cfg_if;
use rand::{rngs::StdRng, Rng, SeedableRng};
use libqoi::{qoi_decode, qoi_encode};
use qoi_fast::{decode_to_vec, encode_to_vec};
use self::common::hash;
struct GenState<const N: usize> {
index: [[u8; N]; 64],
pixels: Vec<u8>,
prev: [u8; N],
len: usize,
}
impl<const N: usize> GenState<N> {
pub fn with_capacity(capacity: usize) -> Self {
Self {
index: [[0; N]; 64],
pixels: Vec::with_capacity(capacity * N),
prev: Self::zero(),
len: 0,
}
}
pub fn write(&mut self, px: [u8; N]) {
self.index[hash(px) as usize] = px;
for i in 0..N {
self.pixels.push(px[i]);
}
self.prev = px;
self.len += 1;
}
pub fn pick_from_index(&self, rng: &mut impl Rng) -> [u8; N] {
self.index[rng.gen_range(0_usize..64)]
}
pub fn zero() -> [u8; N] {
let mut px = [0; N];
if N >= 4 {
px[3] = 0xff;
}
px
}
}
struct ImageGen {
p_new: f64,
p_index: f64,
p_repeat: f64,
p_diff: f64,
p_luma: f64,
}
impl ImageGen {
pub fn new_random(rng: &mut impl Rng) -> Self {
let p = [0; 6].map(|_| rng.gen::<f64>());
let t = p.iter().sum::<f64>();
Self {
p_new: p[0] / t,
p_index: p[1] / t,
p_repeat: p[2] / t,
p_diff: p[3] / t,
p_luma: p[4] / t,
}
}
pub fn generate(&self, rng: &mut impl Rng, channels: usize, min_len: usize) -> Vec<u8> {
match channels {
3 => self.generate_const::<_, 3>(rng, min_len),
4 => self.generate_const::<_, 4>(rng, min_len),
_ => panic!(),
}
}
fn generate_const<R: Rng, const N: usize>(&self, rng: &mut R, min_len: usize) -> Vec<u8> {
let mut s = GenState::<N>::with_capacity(min_len);
let zero = GenState::<N>::zero();
while s.len < min_len {
let mut p = rng.gen_range(0.0..1.0);
if p < self.p_new {
s.write([0; N].map(|_| rng.gen()));
continue;
}
p -= self.p_new;
if p < self.p_index {
let px = s.pick_from_index(rng);
s.write(px);
continue;
}
p -= self.p_index;
if p < self.p_repeat {
let px = s.prev;
let n_repeat = rng.gen_range(1_usize..=70);
for _ in 0..n_repeat {
s.write(px);
}
continue;
}
p -= self.p_repeat;
if p < self.p_diff {
let mut px = s.prev;
let d = [0; 3].map(|_| rng.gen_range(0_u8..4).wrapping_sub(2));
px[0] = px[0].wrapping_add(d[0]);
px[1] = px[1].wrapping_add(d[0]);
px[2] = px[2].wrapping_add(d[0]);
s.write(px);
continue;
}
p -= self.p_diff;
if p < self.p_luma {
let mut px = s.prev;
let vg = rng.gen_range(0_u8..64).wrapping_sub(32);
let vr = rng.gen_range(0_u8..16).wrapping_sub(8).wrapping_add(vg);
let vb = rng.gen_range(0_u8..16).wrapping_sub(8).wrapping_add(vg);
px[0] = px[0].wrapping_add(vr);
px[1] = px[1].wrapping_add(vg);
px[2] = px[2].wrapping_add(vb);
s.write(px);
continue;
}
s.write(zero);
}
s.pixels
}
}
#[test]
fn test_generated() {
let mut rng = StdRng::seed_from_u64(0);
let mut n_pixels = 0;
while n_pixels < 20_000_000 {
let min_len = rng.gen_range(1..=5000);
let channels = rng.gen_range(3..=4);
let gen = ImageGen::new_random(&mut rng);
let img = gen.generate(&mut rng, channels, min_len);
let size = img.len() / channels;
let encoded = encode_to_vec(&img, size as _, 1).unwrap();
let decoded = decode_to_vec(&encoded).unwrap().1;
assert_eq!(&img, &decoded, "qoi-fast: roundtrip fail");
let encoded_c = qoi_encode(&img, size as _, 1, channels as _).unwrap();
let decoded_c = qoi_decode(encoded_c.as_ref(), channels as _).unwrap().1;
assert_eq!(&img, decoded_c.as_ref(), "qoi.h: roundtrip fail");
cfg_if! {
if #[cfg(feature = "reference")] {
assert_eq!(&encoded, encoded_c.as_ref(), "qoi-fast[reference] doesn't match qoi.h");
}
}
let encoded_internal_decoded_c = qoi_decode(encoded.as_ref(), channels as _).unwrap().1;
assert_eq!(encoded_internal_decoded_c.as_ref(), &img, "qoi-fast -> qoi.h: roundtrip fail");
let encoded_c_decoded_internal = decode_to_vec(encoded_c.as_ref()).unwrap().1;
assert_eq!(&encoded_c_decoded_internal, &img, "qoi.h -> qoi-fast: roundtrip fail");
n_pixels += size;
}
}