Files
squoosh/codecs/jxl/dec/jxl_dec.cpp

100 lines
4.3 KiB
C++

#include <emscripten/bind.h>
#include <emscripten/val.h>
#include <jxl/decode.h>
#include "lib/jxl/color_encoding_internal.h"
#include "skcms.h"
using namespace emscripten;
thread_local const val Uint8ClampedArray = val::global("Uint8ClampedArray");
thread_local const val ImageData = val::global("ImageData");
// R, G, B, A
#define COMPONENTS_PER_PIXEL 4
#ifndef JXL_DEBUG_ON_ALL_ERROR
#define JXL_DEBUG_ON_ALL_ERROR 0
#endif
#if JXL_DEBUG_ON_ALL_ERROR
#define EXPECT_TRUE(a) \
if (!(a)) { \
fprintf(stderr, "Assertion failure (%d): %s\n", __LINE__, #a); \
return val::null(); \
}
#define EXPECT_EQ(a, b) \
{ \
int a_ = a; \
int b_ = b; \
if (a_ != b_) { \
fprintf(stderr, "Assertion failure (%d): %s (%d) != %s (%d)\n", __LINE__, #a, a_, #b, b_); \
return val::null(); \
} \
}
#else
#define EXPECT_TRUE(a) \
if (!(a)) { \
return val::null(); \
}
#define EXPECT_EQ(a, b) EXPECT_TRUE((a) == (b));
#endif
val decode(std::string data) {
std::unique_ptr<JxlDecoder,
std::integral_constant<decltype(&JxlDecoderDestroy), JxlDecoderDestroy>>
dec(JxlDecoderCreate(nullptr));
EXPECT_EQ(JXL_DEC_SUCCESS,
JxlDecoderSubscribeEvents(
dec.get(), JXL_DEC_BASIC_INFO | JXL_DEC_COLOR_ENCODING | JXL_DEC_FULL_IMAGE));
auto next_in = (const uint8_t*)data.c_str();
auto avail_in = data.size();
JxlDecoderSetInput(dec.get(), next_in, avail_in);
EXPECT_EQ(JXL_DEC_BASIC_INFO, JxlDecoderProcessInput(dec.get()));
JxlBasicInfo info;
EXPECT_EQ(JXL_DEC_SUCCESS, JxlDecoderGetBasicInfo(dec.get(), &info));
size_t pixel_count = info.xsize * info.ysize;
size_t component_count = pixel_count * COMPONENTS_PER_PIXEL;
EXPECT_EQ(JXL_DEC_COLOR_ENCODING, JxlDecoderProcessInput(dec.get()));
static const JxlPixelFormat format = {COMPONENTS_PER_PIXEL, JXL_TYPE_FLOAT, JXL_LITTLE_ENDIAN, 0};
size_t icc_size;
EXPECT_EQ(JXL_DEC_SUCCESS, JxlDecoderGetICCProfileSize(dec.get(), &format,
JXL_COLOR_PROFILE_TARGET_DATA, &icc_size));
std::vector<uint8_t> icc_profile(icc_size);
EXPECT_EQ(JXL_DEC_SUCCESS,
JxlDecoderGetColorAsICCProfile(dec.get(), &format, JXL_COLOR_PROFILE_TARGET_DATA,
icc_profile.data(), icc_profile.size()));
EXPECT_EQ(JXL_DEC_NEED_IMAGE_OUT_BUFFER, JxlDecoderProcessInput(dec.get()));
size_t buffer_size;
EXPECT_EQ(JXL_DEC_SUCCESS, JxlDecoderImageOutBufferSize(dec.get(), &format, &buffer_size));
EXPECT_EQ(buffer_size, component_count * sizeof(float));
auto float_pixels = std::make_unique<float[]>(component_count);
EXPECT_EQ(JXL_DEC_SUCCESS, JxlDecoderSetImageOutBuffer(dec.get(), &format, float_pixels.get(),
component_count * sizeof(float)));
EXPECT_EQ(JXL_DEC_FULL_IMAGE, JxlDecoderProcessInput(dec.get()));
auto byte_pixels = std::make_unique<uint8_t[]>(component_count);
// Convert to sRGB.
skcms_ICCProfile jxl_profile;
EXPECT_TRUE(skcms_Parse(icc_profile.data(), icc_profile.size(), &jxl_profile));
EXPECT_TRUE(skcms_Transform(
float_pixels.get(), skcms_PixelFormat_RGBA_ffff,
info.alpha_premultiplied ? skcms_AlphaFormat_PremulAsEncoded : skcms_AlphaFormat_Unpremul,
&jxl_profile, byte_pixels.get(), skcms_PixelFormat_RGBA_8888, skcms_AlphaFormat_Unpremul,
skcms_sRGB_profile(), pixel_count));
return ImageData.new_(
Uint8ClampedArray.new_(typed_memory_view(component_count, byte_pixels.get())), info.xsize,
info.ysize);
}
EMSCRIPTEN_BINDINGS(my_module) {
function("decode", &decode);
}