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Merged
csparker247 merged 2 commits into from
Aug 25, 2025
Merged

Image: constify #10

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4b47133
Image: constify
csparker247 Aug 25, 2025
bb5bcf7
Image: Missing std
csparker247 Aug 25, 2025
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52 changes: 29 additions & 23 deletions src/Image.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -8,15 +8,17 @@

using namespace educelab;

namespace
{
// Conversion constants
static constexpr float max_u8{std::numeric_limits<uint8_t>::max()};
static constexpr float max_u16{std::numeric_limits<uint16_t>::max()};
static constexpr float u8_to_u16{max_u16 / max_u8};
static constexpr float u8_to_f32{1.F / max_u8};
static constexpr float u16_to_u8{max_u8 / max_u16};
static constexpr float u16_to_f32{1.F / max_u16};
constexpr float max_u8{std::numeric_limits<std::uint8_t>::max()};
constexpr float max_u16{std::numeric_limits<std::uint16_t>::max()};
constexpr float u8_to_u16{max_u16 / max_u8};
constexpr float u8_to_f32{1.F / max_u8};
constexpr float u16_to_u8{max_u8 / max_u16};
constexpr float u16_to_f32{1.F / max_u16};

static inline auto size_of(const Depth d) -> std::size_t
auto size_of(const Depth d) -> std::size_t
{
switch (d) {
case Depth::None:
Expand All @@ -40,8 +42,9 @@ void depth_cast<std::uint8_t, std::uint16_t>(
{
std::uint8_t tmpI{0};
std::memcpy(&tmpI, in, sizeof(std::uint8_t));
auto f = static_cast<float>(tmpI) * u8_to_u16;
auto tmpO = static_cast<std::uint16_t>(std::max(std::min(f, max_u16), 0.F));
const auto f = static_cast<float>(tmpI) * u8_to_u16;
const auto tmpO =
static_cast<std::uint16_t>(std::max(std::min(f, max_u16), 0.F));
std::memcpy(out, &tmpO, sizeof(std::uint16_t));
}

Expand All @@ -50,7 +53,7 @@ void depth_cast<std::uint8_t, float>(const std::byte* in, std::byte* out)
{
std::uint8_t tmpI{0};
std::memcpy(&tmpI, in, sizeof(std::uint8_t));
auto tmpO = static_cast<float>(tmpI) * u8_to_f32;
const auto tmpO = static_cast<float>(tmpI) * u8_to_f32;
std::memcpy(out, &tmpO, sizeof(float));
}

Expand All @@ -60,8 +63,9 @@ void depth_cast<std::uint16_t, std::uint8_t>(
{
std::uint16_t tmpI{0};
std::memcpy(&tmpI, in, sizeof(std::uint16_t));
auto f = static_cast<float>(tmpI) * u16_to_u8;
auto tmpO = static_cast<std::uint8_t>(std::max(std::min(f, max_u8), 0.F));
const auto f = static_cast<float>(tmpI) * u16_to_u8;
const auto tmpO =
static_cast<std::uint8_t>(std::max(std::min(f, max_u8), 0.F));
std::memcpy(out, &tmpO, sizeof(std::uint8_t));
}

Expand All @@ -70,7 +74,7 @@ void depth_cast<std::uint16_t, float>(const std::byte* in, std::byte* out)
{
std::uint16_t tmpI{0};
std::memcpy(&tmpI, in, sizeof(std::uint16_t));
auto tmpO = static_cast<float>(tmpI) * u16_to_f32;
const auto tmpO = static_cast<float>(tmpI) * u16_to_f32;
std::memcpy(out, &tmpO, sizeof(float));
}

Expand All @@ -79,7 +83,7 @@ void depth_cast<float, std::uint8_t>(const std::byte* in, std::byte* out)
{
float tmpI{0};
std::memcpy(&tmpI, in, sizeof(float));
auto tmpO = static_cast<std::uint8_t>(
const auto tmpO = static_cast<std::uint8_t>(
std::max(std::min(tmpI * max_u8, max_u8), 0.F));
std::memcpy(out, &tmpO, sizeof(std::uint8_t));
}
Expand All @@ -89,7 +93,7 @@ void depth_cast<float, std::uint16_t>(const std::byte* in, std::byte* out)
{
float tmpI{0};
std::memcpy(&tmpI, in, sizeof(float));
auto tmpO = static_cast<std::uint16_t>(
const auto tmpO = static_cast<std::uint16_t>(
std::max(std::min(tmpI * max_u16, max_u16), 0.F));
std::memcpy(out, &tmpO, sizeof(std::uint16_t));
}
Expand All @@ -98,13 +102,13 @@ template <typename TIn, typename TOut>
void pixel_cast(const std::byte* in, std::byte* out, const std::size_t cns)
{
for (std::size_t idx{0}; idx < cns; idx++) {
auto i_idx = idx * sizeof(TIn);
auto o_idx = idx * sizeof(TOut);
const auto i_idx = idx * sizeof(TIn);
const auto o_idx = idx * sizeof(TOut);
depth_cast<TIn, TOut>(&in[i_idx], &out[o_idx]);
}
}

static void convert_pixel(
void convert_pixel(
const std::byte* in,
const Depth inType,
std::byte* out,
Expand Down Expand Up @@ -147,6 +151,7 @@ static void convert_pixel(
throw std::runtime_error("Conversion not supported.");
}
}
} // namespace

Image::Image(
const std::size_t height,
Expand Down Expand Up @@ -205,8 +210,8 @@ auto Image::Convert(const Image& i, const Depth type) -> Image
// Iterate over original image data
for (std::size_t y{0}; y < i.h_; y++) {
for (std::size_t x{0}; x < i.w_; x++) {
auto i_idx = i.unravel_(y, x);
auto r_idx = result.unravel_(y, x);
const auto i_idx = i.unravel_(y, x);
const auto r_idx = result.unravel_(y, x);
convert_pixel(
&i.data_[i_idx], i.type(), &result.data_[r_idx], type, i.cns_);
}
Expand All @@ -220,15 +225,16 @@ auto Image::Gamma(const Image& i, const float gamma) -> Image
auto result = Convert(i, Depth::F32);
for (std::size_t y{0}; y < result.h_; y++) {
for (std::size_t x{0}; x < result.w_; x++) {
auto idx = result.unravel_(y, x);
const auto idx = result.unravel_(y, x);
for (std::size_t c{0}; c < result.cns_; c++) {
auto o = c * sizeof(float);
const auto o = c * sizeof(float);
auto* v = reinterpret_cast<float*>(&result.data_[idx + o]);
*v = std::pow(*v, 1.F / gamma);
}
}
}
return Convert(result, i.type());
result = Convert(result, i.type());
return result;
}

auto Image::convert(const Depth type) const -> Image
Expand Down