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// basisu_enc.cpp
// Copyright (C) 2019-2020 Binomial LLC. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include "basisu_enc.h"
#include "lodepng.h"
#include "basisu_resampler.h"
#include "basisu_resampler_filters.h"
#include "basisu_etc.h"
#include "../transcoder/basisu_transcoder.h"
#include "basisu_bc7enc.h"
#include "apg_bmp.h"
#include "jpgd.h"
#if defined(_WIN32)
// For QueryPerformanceCounter/QueryPerformanceFrequency
#define WIN32_LEAN_AND_MEAN
#define NOMINMAX
#include <windows.h>
#endif
namespace basisu
{
uint64_t interval_timer::g_init_ticks, interval_timer::g_freq;
double interval_timer::g_timer_freq;
uint8_t g_hamming_dist[256] =
{
0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
};
// Encoder library initialization (just call once at startup)
void basisu_encoder_init()
{
basist::basisu_transcoder_init();
pack_etc1_solid_color_init();
//uastc_init();
bc7enc_compress_block_init(); // must be after uastc_init()
}
void error_printf(const char *pFmt, ...)
{
char buf[2048];
va_list args;
va_start(args, pFmt);
#ifdef _WIN32
vsprintf_s(buf, sizeof(buf), pFmt, args);
#else
vsnprintf(buf, sizeof(buf), pFmt, args);
#endif
va_end(args);
fprintf(stderr, "ERROR: %s", buf);
}
#if defined(_WIN32)
inline void query_counter(timer_ticks* pTicks)
{
QueryPerformanceCounter(reinterpret_cast<LARGE_INTEGER*>(pTicks));
}
inline void query_counter_frequency(timer_ticks* pTicks)
{
QueryPerformanceFrequency(reinterpret_cast<LARGE_INTEGER*>(pTicks));
}
#elif defined(__APPLE__)
#include <sys/time.h>
inline void query_counter(timer_ticks* pTicks)
{
struct timeval cur_time;
gettimeofday(&cur_time, NULL);
*pTicks = static_cast<unsigned long long>(cur_time.tv_sec) * 1000000ULL + static_cast<unsigned long long>(cur_time.tv_usec);
}
inline void query_counter_frequency(timer_ticks* pTicks)
{
*pTicks = 1000000;
}
#elif defined(__GNUC__)
#include <sys/timex.h>
inline void query_counter(timer_ticks* pTicks)
{
struct timeval cur_time;
gettimeofday(&cur_time, NULL);
*pTicks = static_cast<unsigned long long>(cur_time.tv_sec) * 1000000ULL + static_cast<unsigned long long>(cur_time.tv_usec);
}
inline void query_counter_frequency(timer_ticks* pTicks)
{
*pTicks = 1000000;
}
#else
#error TODO
#endif
interval_timer::interval_timer() : m_start_time(0), m_stop_time(0), m_started(false), m_stopped(false)
{
if (!g_timer_freq)
init();
}
void interval_timer::start()
{
query_counter(&m_start_time);
m_started = true;
m_stopped = false;
}
void interval_timer::stop()
{
assert(m_started);
query_counter(&m_stop_time);
m_stopped = true;
}
double interval_timer::get_elapsed_secs() const
{
assert(m_started);
if (!m_started)
return 0;
timer_ticks stop_time = m_stop_time;
if (!m_stopped)
query_counter(&stop_time);
timer_ticks delta = stop_time - m_start_time;
return delta * g_timer_freq;
}
void interval_timer::init()
{
if (!g_timer_freq)
{
query_counter_frequency(&g_freq);
g_timer_freq = 1.0f / g_freq;
query_counter(&g_init_ticks);
}
}
timer_ticks interval_timer::get_ticks()
{
if (!g_timer_freq)
init();
timer_ticks ticks;
query_counter(&ticks);
return ticks - g_init_ticks;
}
double interval_timer::ticks_to_secs(timer_ticks ticks)
{
if (!g_timer_freq)
init();
return ticks * g_timer_freq;
}
const uint32_t MAX_32BIT_ALLOC_SIZE = 250000000;
bool load_bmp(const char* pFilename, image& img)
{
int w = 0, h = 0;
unsigned int n_chans = 0;
unsigned char* pImage_data = apg_bmp_read(pFilename, &w, &h, &n_chans);
if ((!pImage_data) || (!w) || (!h) || ((n_chans != 3) && (n_chans != 4)))
{
error_printf("Failed loading .BMP image \"%s\"!\n", pFilename);
if (pImage_data)
apg_bmp_free(pImage_data);
return false;
}
if (sizeof(void *) == sizeof(uint32_t))
{
if ((w * h * n_chans) > MAX_32BIT_ALLOC_SIZE)
{
error_printf("Image \"%s\" is too large (%ux%u) to process in a 32-bit build!\n", pFilename, w, h);
if (pImage_data)
apg_bmp_free(pImage_data);
return false;
}
}
img.resize(w, h);
const uint8_t *pSrc = pImage_data;
for (int y = 0; y < h; y++)
{
color_rgba *pDst = &img(0, y);
for (int x = 0; x < w; x++)
{
pDst->r = pSrc[0];
pDst->g = pSrc[1];
pDst->b = pSrc[2];
pDst->a = (n_chans == 3) ? 255 : pSrc[3];
pSrc += n_chans;
++pDst;
}
}
apg_bmp_free(pImage_data);
return true;
}
bool load_tga(const char* pFilename, image& img)
{
int w = 0, h = 0, n_chans = 0;
uint8_t* pImage_data = read_tga(pFilename, w, h, n_chans);
if ((!pImage_data) || (!w) || (!h) || ((n_chans != 3) && (n_chans != 4)))
{
error_printf("Failed loading .TGA image \"%s\"!\n", pFilename);
if (pImage_data)
free(pImage_data);
return false;
}
if (sizeof(void *) == sizeof(uint32_t))
{
if ((w * h * n_chans) > MAX_32BIT_ALLOC_SIZE)
{
error_printf("Image \"%s\" is too large (%ux%u) to process in a 32-bit build!\n", pFilename, w, h);
if (pImage_data)
free(pImage_data);
return false;
}
}
img.resize(w, h);
const uint8_t *pSrc = pImage_data;
for (int y = 0; y < h; y++)
{
color_rgba *pDst = &img(0, y);
for (int x = 0; x < w; x++)
{
pDst->r = pSrc[0];
pDst->g = pSrc[1];
pDst->b = pSrc[2];
pDst->a = (n_chans == 3) ? 255 : pSrc[3];
pSrc += n_chans;
++pDst;
}
}
free(pImage_data);
return true;
}
bool load_png(const uint8_t *pBuf, size_t buf_size, image &img, const char *pFilename)
{
if (!buf_size)
return false;
unsigned err = 0, w = 0, h = 0;
if (sizeof(void*) == sizeof(uint32_t))
{
// Inspect the image first on 32-bit builds, to see if the image would require too much memory.
lodepng::State state;
err = lodepng_inspect(&w, &h, &state, pBuf, buf_size);
if ((err != 0) || (!w) || (!h))
return false;
const uint32_t exepected_alloc_size = w * h * sizeof(uint32_t);
// If the file is too large on 32-bit builds then just bail now, to prevent causing a memory exception.
if (exepected_alloc_size >= MAX_32BIT_ALLOC_SIZE)
{
error_printf("Image \"%s\" is too large (%ux%u) to process in a 32-bit build!\n", (pFilename != nullptr) ? pFilename : "<memory>", w, h);
return false;
}
w = h = 0;
}
std::vector<uint8_t> out;
err = lodepng::decode(out, w, h, pBuf, buf_size);
if ((err != 0) || (!w) || (!h))
return false;
if (out.size() != (w * h * 4))
return false;
img.resize(w, h);
memcpy(img.get_ptr(), &out[0], out.size());
return true;
}
bool load_png(const char* pFilename, image& img)
{
std::vector<uint8_t> buffer;
unsigned err = lodepng::load_file(buffer, std::string(pFilename));
if (err)
return false;
return load_png(buffer.data(), buffer.size(), img, pFilename);
}
bool load_jpg(const char *pFilename, image& img)
{
int width = 0, height = 0, actual_comps = 0;
uint8_t *pImage_data = jpgd::decompress_jpeg_image_from_file(pFilename, &width, &height, &actual_comps, 4, jpgd::jpeg_decoder::cFlagLinearChromaFiltering);
if (!pImage_data)
return false;
img.init(pImage_data, width, height, 4);
free(pImage_data);
return true;
}
bool load_image(const char* pFilename, image& img)
{
std::string ext(string_get_extension(std::string(pFilename)));
if (ext.length() == 0)
return false;
const char *pExt = ext.c_str();
if (strcasecmp(pExt, "png") == 0)
return load_png(pFilename, img);
if (strcasecmp(pExt, "bmp") == 0)
return load_bmp(pFilename, img);
if (strcasecmp(pExt, "tga") == 0)
return load_tga(pFilename, img);
if ( (strcasecmp(pExt, "jpg") == 0) || (strcasecmp(pExt, "jfif") == 0) || (strcasecmp(pExt, "jpeg") == 0) )
return load_jpg(pFilename, img);
return false;
}
bool save_png(const char* pFilename, const image &img, uint32_t image_save_flags, uint32_t grayscale_comp)
{
if (!img.get_total_pixels())
return false;
const uint32_t MAX_PNG_IMAGE_DIM = 32768;
if ((img.get_width() > MAX_PNG_IMAGE_DIM) || (img.get_height() > MAX_PNG_IMAGE_DIM))
return false;
std::vector<uint8_t> out;
unsigned err = 0;
if (image_save_flags & cImageSaveGrayscale)
{
uint8_vec g_pixels(img.get_width() * img.get_height());
uint8_t *pDst = &g_pixels[0];
for (uint32_t y = 0; y < img.get_height(); y++)
for (uint32_t x = 0; x < img.get_width(); x++)
*pDst++ = img(x, y)[grayscale_comp];
err = lodepng::encode(out, (const uint8_t*)&g_pixels[0], img.get_width(), img.get_height(), LCT_GREY, 8);
}
else
{
bool has_alpha = img.has_alpha();
if ((!has_alpha) || ((image_save_flags & cImageSaveIgnoreAlpha) != 0))
{
const uint64_t total_bytes = (uint64_t)img.get_width() * 3U * (uint64_t)img.get_height();
uint8_vec rgb_pixels(static_cast<size_t>(total_bytes));
uint8_t *pDst = &rgb_pixels[0];
for (uint32_t y = 0; y < img.get_height(); y++)
{
for (uint32_t x = 0; x < img.get_width(); x++)
{
const color_rgba& c = img(x, y);
pDst[0] = c.r;
pDst[1] = c.g;
pDst[2] = c.b;
pDst += 3;
}
}
err = lodepng::encode(out, (const uint8_t*)& rgb_pixels[0], img.get_width(), img.get_height(), LCT_RGB, 8);
}
else
{
err = lodepng::encode(out, (const uint8_t*)img.get_ptr(), img.get_width(), img.get_height(), LCT_RGBA, 8);
}
}
err = lodepng::save_file(out, std::string(pFilename));
if (err)
return false;
return true;
}
bool read_file_to_vec(const char* pFilename, uint8_vec& data)
{
FILE* pFile = nullptr;
#ifdef _WIN32
fopen_s(&pFile, pFilename, "rb");
#else
pFile = fopen(pFilename, "rb");
#endif
if (!pFile)
return false;
fseek(pFile, 0, SEEK_END);
#ifdef _WIN32
int64_t filesize = _ftelli64(pFile);
#else
int64_t filesize = ftello(pFile);
#endif
if (filesize < 0)
{
fclose(pFile);
return false;
}
fseek(pFile, 0, SEEK_SET);
if (sizeof(size_t) == sizeof(uint32_t))
{
if (filesize > 0x70000000)
{
// File might be too big to load safely in one alloc
fclose(pFile);
return false;
}
}
data.resize((size_t)filesize);
if (filesize)
{
if (fread(&data[0], 1, (size_t)filesize, pFile) != (size_t)filesize)
{
fclose(pFile);
return false;
}
}
fclose(pFile);
return true;
}
bool write_data_to_file(const char* pFilename, const void* pData, size_t len)
{
FILE* pFile = nullptr;
#ifdef _WIN32
fopen_s(&pFile, pFilename, "wb");
#else
pFile = fopen(pFilename, "wb");
#endif
if (!pFile)
return false;
if (len)
{
if (fwrite(pData, 1, len, pFile) != len)
{
fclose(pFile);
return false;
}
}
return fclose(pFile) != EOF;
}
float linear_to_srgb(float l)
{
assert(l >= 0.0f && l <= 1.0f);
if (l < .0031308f)
return saturate(l * 12.92f);
else
return saturate(1.055f * powf(l, 1.0f/2.4f) - .055f);
}
float srgb_to_linear(float s)
{
assert(s >= 0.0f && s <= 1.0f);
if (s < .04045f)
return saturate(s * (1.0f/12.92f));
else
return saturate(powf((s + .055f) * (1.0f/1.055f), 2.4f));
}
bool image_resample(const image &src, image &dst, bool srgb,
const char *pFilter, float filter_scale,
bool wrapping,
uint32_t first_comp, uint32_t num_comps)
{
assert((first_comp + num_comps) <= 4);
const int cMaxComps = 4;
const uint32_t src_w = src.get_width(), src_h = src.get_height();
const uint32_t dst_w = dst.get_width(), dst_h = dst.get_height();
if (maximum(src_w, src_h) > BASISU_RESAMPLER_MAX_DIMENSION)
{
printf("Image is too large!\n");
return false;
}
if (!src_w || !src_h || !dst_w || !dst_h)
return false;
if ((num_comps < 1) || (num_comps > cMaxComps))
return false;
if ((minimum(dst_w, dst_h) < 1) || (maximum(dst_w, dst_h) > BASISU_RESAMPLER_MAX_DIMENSION))
{
printf("Image is too large!\n");
return false;
}
if ((src_w == dst_w) && (src_h == dst_h))
{
dst = src;
return true;
}
float srgb_to_linear_table[256];
if (srgb)
{
for (int i = 0; i < 256; ++i)
srgb_to_linear_table[i] = srgb_to_linear((float)i * (1.0f/255.0f));
}
const int LINEAR_TO_SRGB_TABLE_SIZE = 8192;
uint8_t linear_to_srgb_table[LINEAR_TO_SRGB_TABLE_SIZE];
if (srgb)
{
for (int i = 0; i < LINEAR_TO_SRGB_TABLE_SIZE; ++i)
linear_to_srgb_table[i] = (uint8_t)clamp<int>((int)(255.0f * linear_to_srgb((float)i * (1.0f / (LINEAR_TO_SRGB_TABLE_SIZE - 1))) + .5f), 0, 255);
}
std::vector<float> samples[cMaxComps];
Resampler *resamplers[cMaxComps];
resamplers[0] = new Resampler(src_w, src_h, dst_w, dst_h,
wrapping ? Resampler::BOUNDARY_WRAP : Resampler::BOUNDARY_CLAMP, 0.0f, 1.0f,
pFilter, nullptr, nullptr, filter_scale, filter_scale, 0, 0);
samples[0].resize(src_w);
for (uint32_t i = 1; i < num_comps; ++i)
{
resamplers[i] = new Resampler(src_w, src_h, dst_w, dst_h,
wrapping ? Resampler::BOUNDARY_WRAP : Resampler::BOUNDARY_CLAMP, 0.0f, 1.0f,
pFilter, resamplers[0]->get_clist_x(), resamplers[0]->get_clist_y(), filter_scale, filter_scale, 0, 0);
samples[i].resize(src_w);
}
uint32_t dst_y = 0;
for (uint32_t src_y = 0; src_y < src_h; ++src_y)
{
const color_rgba *pSrc = &src(0, src_y);
// Put source lines into resampler(s)
for (uint32_t x = 0; x < src_w; ++x)
{
for (uint32_t c = 0; c < num_comps; ++c)
{
const uint32_t comp_index = first_comp + c;
const uint32_t v = (*pSrc)[comp_index];
if (!srgb || (comp_index == 3))
samples[c][x] = v * (1.0f / 255.0f);
else
samples[c][x] = srgb_to_linear_table[v];
}
pSrc++;
}
for (uint32_t c = 0; c < num_comps; ++c)
{
if (!resamplers[c]->put_line(&samples[c][0]))
{
for (uint32_t i = 0; i < num_comps; i++)
delete resamplers[i];
return false;
}
}
// Now retrieve any output lines
for (;;)
{
uint32_t c;
for (c = 0; c < num_comps; ++c)
{
const uint32_t comp_index = first_comp + c;
const float *pOutput_samples = resamplers[c]->get_line();
if (!pOutput_samples)
break;
const bool linear_flag = !srgb || (comp_index == 3);
color_rgba *pDst = &dst(0, dst_y);
for (uint32_t x = 0; x < dst_w; x++)
{
// TODO: Add dithering
if (linear_flag)
{
int j = (int)(255.0f * pOutput_samples[x] + .5f);
(*pDst)[comp_index] = (uint8_t)clamp<int>(j, 0, 255);
}
else
{
int j = (int)((LINEAR_TO_SRGB_TABLE_SIZE - 1) * pOutput_samples[x] + .5f);
(*pDst)[comp_index] = linear_to_srgb_table[clamp<int>(j, 0, LINEAR_TO_SRGB_TABLE_SIZE - 1)];
}
pDst++;
}
}
if (c < num_comps)
break;
++dst_y;
}
}
for (uint32_t i = 0; i < num_comps; ++i)
delete resamplers[i];
return true;
}
void canonical_huffman_calculate_minimum_redundancy(sym_freq *A, int num_syms)
{
// See the paper "In-Place Calculation of Minimum Redundancy Codes" by Moffat and Katajainen
if (!num_syms)
return;
if (1 == num_syms)
{
A[0].m_key = 1;
return;
}
A[0].m_key += A[1].m_key;
int s = 2, r = 0, next;
for (next = 1; next < (num_syms - 1); ++next)
{
if ((s >= num_syms) || (A[r].m_key < A[s].m_key))
{
A[next].m_key = A[r].m_key;
A[r].m_key = next;
++r;
}
else
{
A[next].m_key = A[s].m_key;
++s;
}
if ((s >= num_syms) || ((r < next) && A[r].m_key < A[s].m_key))
{
A[next].m_key = A[next].m_key + A[r].m_key;
A[r].m_key = next;
++r;
}
else
{
A[next].m_key = A[next].m_key + A[s].m_key;
++s;
}
}
A[num_syms - 2].m_key = 0;
for (next = num_syms - 3; next >= 0; --next)
{
A[next].m_key = 1 + A[A[next].m_key].m_key;
}
int num_avail = 1, num_used = 0, depth = 0;
r = num_syms - 2;
next = num_syms - 1;
while (num_avail > 0)
{
for ( ; (r >= 0) && ((int)A[r].m_key == depth); ++num_used, --r )
;
for ( ; num_avail > num_used; --next, --num_avail)
A[next].m_key = depth;
num_avail = 2 * num_used;
num_used = 0;
++depth;
}
}
void canonical_huffman_enforce_max_code_size(int *pNum_codes, int code_list_len, int max_code_size)
{
int i;
uint32_t total = 0;
if (code_list_len <= 1)
return;
for (i = max_code_size + 1; i <= cHuffmanMaxSupportedInternalCodeSize; i++)
pNum_codes[max_code_size] += pNum_codes[i];
for (i = max_code_size; i > 0; i--)
total += (((uint32_t)pNum_codes[i]) << (max_code_size - i));
while (total != (1UL << max_code_size))
{
pNum_codes[max_code_size]--;
for (i = max_code_size - 1; i > 0; i--)
{
if (pNum_codes[i])
{
pNum_codes[i]--;
pNum_codes[i + 1] += 2;
break;
}
}
total--;
}
}
sym_freq *canonical_huffman_radix_sort_syms(uint32_t num_syms, sym_freq *pSyms0, sym_freq *pSyms1)
{
uint32_t total_passes = 2, pass_shift, pass, i, hist[256 * 2];
sym_freq *pCur_syms = pSyms0, *pNew_syms = pSyms1;
clear_obj(hist);
for (i = 0; i < num_syms; i++)
{
uint32_t freq = pSyms0[i].m_key;
// We scale all input frequencies to 16-bits.
assert(freq <= UINT16_MAX);
hist[freq & 0xFF]++;
hist[256 + ((freq >> 8) & 0xFF)]++;
}
while ((total_passes > 1) && (num_syms == hist[(total_passes - 1) * 256]))
total_passes--;
for (pass_shift = 0, pass = 0; pass < total_passes; pass++, pass_shift += 8)
{
const uint32_t *pHist = &hist[pass << 8];
uint32_t offsets[256], cur_ofs = 0;
for (i = 0; i < 256; i++)
{
offsets[i] = cur_ofs;
cur_ofs += pHist[i];
}
for (i = 0; i < num_syms; i++)
pNew_syms[offsets[(pCur_syms[i].m_key >> pass_shift) & 0xFF]++] = pCur_syms[i];
sym_freq *t = pCur_syms;
pCur_syms = pNew_syms;
pNew_syms = t;
}
return pCur_syms;
}
bool huffman_encoding_table::init(uint32_t num_syms, const uint16_t *pFreq, uint32_t max_code_size)
{
if (max_code_size > cHuffmanMaxSupportedCodeSize)
return false;
if ((!num_syms) || (num_syms > cHuffmanMaxSyms))
return false;
uint32_t total_used_syms = 0;
for (uint32_t i = 0; i < num_syms; i++)
if (pFreq[i])
total_used_syms++;
if (!total_used_syms)
return false;
std::vector<sym_freq> sym_freq0(total_used_syms), sym_freq1(total_used_syms);
for (uint32_t i = 0, j = 0; i < num_syms; i++)
{
if (pFreq[i])
{
sym_freq0[j].m_key = pFreq[i];
sym_freq0[j++].m_sym_index = static_cast<uint16_t>(i);
}
}
sym_freq *pSym_freq = canonical_huffman_radix_sort_syms(total_used_syms, &sym_freq0[0], &sym_freq1[0]);
canonical_huffman_calculate_minimum_redundancy(pSym_freq, total_used_syms);
int num_codes[cHuffmanMaxSupportedInternalCodeSize + 1];
clear_obj(num_codes);
for (uint32_t i = 0; i < total_used_syms; i++)
{
if (pSym_freq[i].m_key > cHuffmanMaxSupportedInternalCodeSize)
return false;
num_codes[pSym_freq[i].m_key]++;
}
canonical_huffman_enforce_max_code_size(num_codes, total_used_syms, max_code_size);
m_code_sizes.resize(0);
m_code_sizes.resize(num_syms);
m_codes.resize(0);
m_codes.resize(num_syms);
for (uint32_t i = 1, j = total_used_syms; i <= max_code_size; i++)
for (uint32_t l = num_codes[i]; l > 0; l--)
m_code_sizes[pSym_freq[--j].m_sym_index] = static_cast<uint8_t>(i);
uint32_t next_code[cHuffmanMaxSupportedInternalCodeSize + 1];
next_code[1] = 0;
for (uint32_t j = 0, i = 2; i <= max_code_size; i++)
next_code[i] = j = ((j + num_codes[i - 1]) << 1);
for (uint32_t i = 0; i < num_syms; i++)
{
uint32_t rev_code = 0, code, code_size;
if ((code_size = m_code_sizes[i]) == 0)
continue;
if (code_size > cHuffmanMaxSupportedInternalCodeSize)
return false;
code = next_code[code_size]++;
for (uint32_t l = code_size; l > 0; l--, code >>= 1)
rev_code = (rev_code << 1) | (code & 1);
m_codes[i] = static_cast<uint16_t>(rev_code);
}
return true;
}
bool huffman_encoding_table::init(uint32_t num_syms, const uint32_t *pSym_freq, uint32_t max_code_size)
{
if ((!num_syms) || (num_syms > cHuffmanMaxSyms))
return false;
uint16_vec sym_freq(num_syms);
uint32_t max_freq = 0;
for (uint32_t i = 0; i < num_syms; i++)
max_freq = maximum(max_freq, pSym_freq[i]);
if (max_freq < UINT16_MAX)
{
for (uint32_t i = 0; i < num_syms; i++)
sym_freq[i] = static_cast<uint16_t>(pSym_freq[i]);
}
else
{
for (uint32_t i = 0; i < num_syms; i++)
{
if (pSym_freq[i])
{
uint32_t f = static_cast<uint32_t>((static_cast<uint64_t>(pSym_freq[i]) * 65534U + (max_freq >> 1)) / max_freq);
sym_freq[i] = static_cast<uint16_t>(clamp<uint32_t>(f, 1, 65534));
}
}
}
return init(num_syms, &sym_freq[0], max_code_size);
}
void bitwise_coder::end_nonzero_run(uint16_vec &syms, uint32_t &run_size, uint32_t len)
{
if (run_size)
{
if (run_size < cHuffmanSmallRepeatSizeMin)
{
while (run_size--)
syms.push_back(static_cast<uint16_t>(len));
}
else if (run_size <= cHuffmanSmallRepeatSizeMax)
{
syms.push_back(static_cast<uint16_t>(cHuffmanSmallRepeatCode | ((run_size - cHuffmanSmallRepeatSizeMin) << 6)));
}
else
{
assert((run_size >= cHuffmanBigRepeatSizeMin) && (run_size <= cHuffmanBigRepeatSizeMax));
syms.push_back(static_cast<uint16_t>(cHuffmanBigRepeatCode | ((run_size - cHuffmanBigRepeatSizeMin) << 6)));
}
}
run_size = 0;
}
void bitwise_coder::end_zero_run(uint16_vec &syms, uint32_t &run_size)
{
if (run_size)
{
if (run_size < cHuffmanSmallZeroRunSizeMin)
{
while (run_size--)
syms.push_back(0);
}
else if (run_size <= cHuffmanSmallZeroRunSizeMax)
{
syms.push_back(static_cast<uint16_t>(cHuffmanSmallZeroRunCode | ((run_size - cHuffmanSmallZeroRunSizeMin) << 6)));
}
else
{
assert((run_size >= cHuffmanBigZeroRunSizeMin) && (run_size <= cHuffmanBigZeroRunSizeMax));
syms.push_back(static_cast<uint16_t>(cHuffmanBigZeroRunCode | ((run_size - cHuffmanBigZeroRunSizeMin) << 6)));
}
}
run_size = 0;
}
uint32_t bitwise_coder::emit_huffman_table(const huffman_encoding_table &tab)
{
const uint64_t start_bits = m_total_bits;
const uint8_vec &code_sizes = tab.get_code_sizes();
uint32_t total_used = tab.get_total_used_codes();
put_bits(total_used, cHuffmanMaxSymsLog2);
if (!total_used)
return 0;
uint16_vec syms;
syms.reserve(total_used + 16);
uint32_t prev_code_len = UINT_MAX, zero_run_size = 0, nonzero_run_size = 0;
for (uint32_t i = 0; i <= total_used; ++i)
{
const uint32_t code_len = (i == total_used) ? 0xFF : code_sizes[i];
assert((code_len == 0xFF) || (code_len <= 16));
if (code_len)
{
end_zero_run(syms, zero_run_size);
if (code_len != prev_code_len)
{
end_nonzero_run(syms, nonzero_run_size, prev_code_len);
if (code_len != 0xFF)
syms.push_back(static_cast<uint16_t>(code_len));
}
else if (++nonzero_run_size == cHuffmanBigRepeatSizeMax)
end_nonzero_run(syms, nonzero_run_size, prev_code_len);
}
else
{
end_nonzero_run(syms, nonzero_run_size, prev_code_len);
if (++zero_run_size == cHuffmanBigZeroRunSizeMax)
end_zero_run(syms, zero_run_size);
}
prev_code_len = code_len;
}
histogram h(cHuffmanTotalCodelengthCodes);
for (uint32_t i = 0; i < syms.size(); i++)
h.inc(syms[i] & 63);
huffman_encoding_table ct;
if (!ct.init(h, 7))
return 0;
assert(cHuffmanTotalSortedCodelengthCodes == cHuffmanTotalCodelengthCodes);
uint32_t total_codelength_codes;
for (total_codelength_codes = cHuffmanTotalSortedCodelengthCodes; total_codelength_codes > 0; total_codelength_codes--)
if (ct.get_code_sizes()[g_huffman_sorted_codelength_codes[total_codelength_codes - 1]])
break;
assert(total_codelength_codes);
put_bits(total_codelength_codes, 5);
for (uint32_t i = 0; i < total_codelength_codes; i++)
put_bits(ct.get_code_sizes()[g_huffman_sorted_codelength_codes[i]], 3);
for (uint32_t i = 0; i < syms.size(); ++i)
{
const uint32_t l = syms[i] & 63, e = syms[i] >> 6;
put_code(l, ct);
if (l == cHuffmanSmallZeroRunCode)
put_bits(e, cHuffmanSmallZeroRunExtraBits);
else if (l == cHuffmanBigZeroRunCode)
put_bits(e, cHuffmanBigZeroRunExtraBits);
else if (l == cHuffmanSmallRepeatCode)
put_bits(e, cHuffmanSmallRepeatExtraBits);
else if (l == cHuffmanBigRepeatCode)
put_bits(e, cHuffmanBigRepeatExtraBits);
}
return (uint32_t)(m_total_bits - start_bits);
}
bool huffman_test(int rand_seed)
{
histogram h(19);
// Feed in a fibonacci sequence to force large codesizes
h[0] += 1; h[1] += 1; h[2] += 2; h[3] += 3;
h[4] += 5; h[5] += 8; h[6] += 13; h[7] += 21;
h[8] += 34; h[9] += 55; h[10] += 89; h[11] += 144;
h[12] += 233; h[13] += 377; h[14] += 610; h[15] += 987;
h[16] += 1597; h[17] += 2584; h[18] += 4181;
huffman_encoding_table etab;
etab.init(h, 16);
{
bitwise_coder c;
c.init(1024);
c.emit_huffman_table(etab);
for (int i = 0; i < 19; i++)
c.put_code(i, etab);
c.flush();
basist::bitwise_decoder d;
d.init(&c.get_bytes()[0], static_cast<uint32_t>(c.get_bytes().size()));
basist::huffman_decoding_table dtab;
bool success = d.read_huffman_table(dtab);
if (!success)
{
assert(0);
printf("Failure 5\n");
return false;
}
for (uint32_t i = 0; i < 19; i++)
{
uint32_t s = d.decode_huffman(dtab);
if (s != i)
{
assert(0);
printf("Failure 5\n");
return false;
}
}
}
basisu::rand r;
r.seed(rand_seed);
for (int iter = 0; iter < 500000; iter++)
{
printf("%u\n", iter);
uint32_t max_sym = r.irand(0, 8193);
uint32_t num_codes = r.irand(1, 10000);
uint_vec syms(num_codes);
for (uint32_t i = 0; i < num_codes; i++)
{
if (r.bit())
syms[i] = r.irand(0, max_sym);
else
{
int s = (int)(r.gaussian((float)max_sym / 2, (float)maximum<int>(1, max_sym / 2)) + .5f);
s = basisu::clamp<int>(s, 0, max_sym);
syms[i] = s;
}
}
histogram h1(max_sym + 1);
for (uint32_t i = 0; i < num_codes; i++)
h1[syms[i]]++;
huffman_encoding_table etab2;
if (!etab2.init(h1, 16))
{
assert(0);
printf("Failed 0\n");
return false;
}
bitwise_coder c;
c.init(1024);
c.emit_huffman_table(etab2);
for (uint32_t i = 0; i < num_codes; i++)
c.put_code(syms[i], etab2);
c.flush();
basist::bitwise_decoder d;
d.init(&c.get_bytes()[0], (uint32_t)c.get_bytes().size());
basist::huffman_decoding_table dtab;
bool success = d.read_huffman_table(dtab);
if (!success)
{
assert(0);
printf("Failed 2\n");
return false;
}
for (uint32_t i = 0; i < num_codes; i++)
{
uint32_t s = d.decode_huffman(dtab);
if (s != syms[i])
{
assert(0);
printf("Failed 4\n");
return false;
}
}
}
return true;
}
void palette_index_reorderer::init(uint32_t num_indices, const uint32_t *pIndices, uint32_t num_syms, pEntry_dist_func pDist_func, void *pCtx, float dist_func_weight)
{
assert((num_syms > 0) && (num_indices > 0));
assert((dist_func_weight >= 0.0f) && (dist_func_weight <= 1.0f));
clear();
m_remap_table.resize(num_syms);
m_entries_picked.reserve(num_syms);
m_total_count_to_picked.resize(num_syms);
if (num_indices <= 1)
return;
prepare_hist(num_syms, num_indices, pIndices);
find_initial(num_syms);
while (m_entries_to_do.size())
{
// Find the best entry to move into the picked list.
uint32_t best_entry;
double best_count;
find_next_entry(best_entry, best_count, pDist_func, pCtx, dist_func_weight);
// We now have chosen an entry to place in the picked list, now determine which side it goes on.
const uint32_t entry_to_move = m_entries_to_do[best_entry];
float side = pick_side(num_syms, entry_to_move, pDist_func, pCtx, dist_func_weight);
// Put entry_to_move either on the "left" or "right" side of the picked entries
if (side <= 0)
m_entries_picked.push_back(entry_to_move);
else
m_entries_picked.insert(m_entries_picked.begin(), entry_to_move);
// Erase best_entry from the todo list
m_entries_to_do.erase(m_entries_to_do.begin() + best_entry);
// We've just moved best_entry to the picked list, so now we need to update m_total_count_to_picked[] to factor the additional count to best_entry
for (uint32_t i = 0; i < m_entries_to_do.size(); i++)
m_total_count_to_picked[m_entries_to_do[i]] += get_hist(m_entries_to_do[i], entry_to_move, num_syms);
}
for (uint32_t i = 0; i < num_syms; i++)
m_remap_table[m_entries_picked[i]] = i;
}
void palette_index_reorderer::prepare_hist(uint32_t num_syms, uint32_t num_indices, const uint32_t *pIndices)
{
m_hist.resize(0);
m_hist.resize(num_syms * num_syms);
for (uint32_t i = 0; i < num_indices; i++)
{
const uint32_t idx = pIndices[i];
inc_hist(idx, (i < (num_indices - 1)) ? pIndices[i + 1] : -1, num_syms);
inc_hist(idx, (i > 0) ? pIndices[i - 1] : -1, num_syms);
}
}
void palette_index_reorderer::find_initial(uint32_t num_syms)
{
uint32_t max_count = 0, max_index = 0;
for (uint32_t i = 0; i < num_syms * num_syms; i++)
if (m_hist[i] > max_count)
max_count = m_hist[i], max_index = i;
uint32_t a = max_index / num_syms, b = max_index % num_syms;
m_entries_picked.push_back(a);
m_entries_picked.push_back(b);
for (uint32_t i = 0; i < num_syms; i++)
if ((i != b) && (i != a))
m_entries_to_do.push_back(i);
for (uint32_t i = 0; i < m_entries_to_do.size(); i++)
for (uint32_t j = 0; j < m_entries_picked.size(); j++)
m_total_count_to_picked[m_entries_to_do[i]] += get_hist(m_entries_to_do[i], m_entries_picked[j], num_syms);
}
void palette_index_reorderer::find_next_entry(uint32_t &best_entry, double &best_count, pEntry_dist_func pDist_func, void *pCtx, float dist_func_weight)
{
best_entry = 0;
best_count = 0;
for (uint32_t i = 0; i < m_entries_to_do.size(); i++)
{
const uint32_t u = m_entries_to_do[i];
double total_count = m_total_count_to_picked[u];
if (pDist_func)
{
float w = maximum<float>((*pDist_func)(u, m_entries_picked.front(), pCtx), (*pDist_func)(u, m_entries_picked.back(), pCtx));
assert((w >= 0.0f) && (w <= 1.0f));
total_count = (total_count + 1.0f) * lerp(1.0f - dist_func_weight, 1.0f + dist_func_weight, w);
}
if (total_count <= best_count)
continue;
best_entry = i;
best_count = total_count;
}
}
float palette_index_reorderer::pick_side(uint32_t num_syms, uint32_t entry_to_move, pEntry_dist_func pDist_func, void *pCtx, float dist_func_weight)
{
float which_side = 0;
int l_count = 0, r_count = 0;
for (uint32_t j = 0; j < m_entries_picked.size(); j++)
{
const int count = get_hist(entry_to_move, m_entries_picked[j], num_syms), r = ((int)m_entries_picked.size() + 1 - 2 * (j + 1));
which_side += static_cast<float>(r * count);
if (r >= 0)
l_count += r * count;
else
r_count += -r * count;
}
if (pDist_func)
{
float w_left = lerp(1.0f - dist_func_weight, 1.0f + dist_func_weight, (*pDist_func)(entry_to_move, m_entries_picked.front(), pCtx));
float w_right = lerp(1.0f - dist_func_weight, 1.0f + dist_func_weight, (*pDist_func)(entry_to_move, m_entries_picked.back(), pCtx));
which_side = w_left * l_count - w_right * r_count;
}
return which_side;
}
void image_metrics::calc(const image &a, const image &b, uint32_t first_chan, uint32_t total_chans, bool avg_comp_error, bool use_601_luma)
{
assert((first_chan < 4U) && (first_chan + total_chans <= 4U));
const uint32_t width = std::min(a.get_width(), b.get_width());
const uint32_t height = std::min(a.get_height(), b.get_height());
double hist[256];
clear_obj(hist);
for (uint32_t y = 0; y < height; y++)
{
for (uint32_t x = 0; x < width; x++)
{
const color_rgba &ca = a(x, y), &cb = b(x, y);
if (total_chans)
{
for (uint32_t c = 0; c < total_chans; c++)
hist[iabs(ca[first_chan + c] - cb[first_chan + c])]++;
}
else
{
if (use_601_luma)
hist[iabs(ca.get_601_luma() - cb.get_601_luma())]++;
else
hist[iabs(ca.get_709_luma() - cb.get_709_luma())]++;
}
}
}
m_max = 0;
double sum = 0.0f, sum2 = 0.0f;
for (uint32_t i = 0; i < 256; i++)
{
if (hist[i])
{
m_max = std::max<float>(m_max, (float)i);
double v = i * hist[i];
sum += v;
sum2 += i * v;
}
}
double total_values = (double)width * (double)height;
if (avg_comp_error)
total_values *= (double)clamp<uint32_t>(total_chans, 1, 4);
m_mean = (float)clamp<double>(sum / total_values, 0.0f, 255.0);
m_mean_squared = (float)clamp<double>(sum2 / total_values, 0.0f, 255.0f * 255.0f);
m_rms = (float)sqrt(m_mean_squared);
m_psnr = m_rms ? (float)clamp<double>(log10(255.0 / m_rms) * 20.0f, 0.0f, 100.0f) : 100.0f;
}
void fill_buffer_with_random_bytes(void *pBuf, size_t size, uint32_t seed)
{
rand r(seed);
uint8_t *pDst = static_cast<uint8_t *>(pBuf);
while (size >= sizeof(uint32_t))
{
*(uint32_t *)pDst = r.urand32();
pDst += sizeof(uint32_t);
size -= sizeof(uint32_t);
}
while (size)
{
*pDst++ = r.byte();
size--;
}
}
uint32_t hash_hsieh(const uint8_t *pBuf, size_t len)
{
if (!pBuf || !len)
return 0;
uint32_t h = static_cast<uint32_t>(len);
const uint32_t bytes_left = len & 3;
len >>= 2;
while (len--)
{
const uint16_t *pWords = reinterpret_cast<const uint16_t *>(pBuf);
h += pWords[0];
const uint32_t t = (pWords[1] << 11) ^ h;
h = (h << 16) ^ t;
pBuf += sizeof(uint32_t);
h += h >> 11;
}
switch (bytes_left)
{
case 1:
h += *reinterpret_cast<const signed char*>(pBuf);
h ^= h << 10;
h += h >> 1;
break;
case 2:
h += *reinterpret_cast<const uint16_t *>(pBuf);
h ^= h << 11;
h += h >> 17;
break;
case 3:
h += *reinterpret_cast<const uint16_t *>(pBuf);
h ^= h << 16;
h ^= (static_cast<signed char>(pBuf[sizeof(uint16_t)])) << 18;
h += h >> 11;
break;
default:
break;
}
h ^= h << 3;
h += h >> 5;
h ^= h << 4;
h += h >> 17;
h ^= h << 25;
h += h >> 6;
return h;
}
job_pool::job_pool(uint32_t num_threads) :
m_num_active_jobs(0),
m_kill_flag(false)
{
assert(num_threads >= 1U);
debug_printf("job_pool::job_pool: %u total threads\n", num_threads);
if (num_threads > 1)
{
m_threads.resize(num_threads - 1);
for (int i = 0; i < ((int)num_threads - 1); i++)
m_threads[i] = std::thread([this, i] { job_thread(i); });
}
}
job_pool::~job_pool()
{
debug_printf("job_pool::~job_pool\n");
// Notify all workers that they need to die right now.
m_kill_flag = true;
m_has_work.notify_all();
// Wait for all workers to die.
for (uint32_t i = 0; i < m_threads.size(); i++)
m_threads[i].join();
}
void job_pool::add_job(const std::function<void()>& job)
{
std::unique_lock<std::mutex> lock(m_mutex);
m_queue.emplace_back(job);
const size_t queue_size = m_queue.size();
lock.unlock();
if (queue_size > 1)
m_has_work.notify_one();
}
void job_pool::add_job(std::function<void()>&& job)
{
std::unique_lock<std::mutex> lock(m_mutex);
m_queue.emplace_back(std::move(job));
const size_t queue_size = m_queue.size();
lock.unlock();
if (queue_size > 1)
{
m_has_work.notify_one();
}
}
void job_pool::wait_for_all()
{
std::unique_lock<std::mutex> lock(m_mutex);
// Drain the job queue on the calling thread.
while (!m_queue.empty())
{
std::function<void()> job(m_queue.back());
m_queue.pop_back();
lock.unlock();
job();
lock.lock();
}
// The queue is empty, now wait for all active jobs to finish up.
m_no_more_jobs.wait(lock, [this]{ return !m_num_active_jobs; } );
}
void job_pool::job_thread(uint32_t index)
{
debug_printf("job_pool::job_thread: starting %u\n", index);
while (true)
{
std::unique_lock<std::mutex> lock(m_mutex);
// Wait for any jobs to be issued.
m_has_work.wait(lock, [this] { return m_kill_flag || m_queue.size(); } );
// Check to see if we're supposed to exit.
if (m_kill_flag)
break;
// Get the job and execute it.
std::function<void()> job(m_queue.back());
m_queue.pop_back();
++m_num_active_jobs;
lock.unlock();
job();
lock.lock();
--m_num_active_jobs;
// Now check if there are no more jobs remaining.
const bool all_done = m_queue.empty() && !m_num_active_jobs;
lock.unlock();
if (all_done)
m_no_more_jobs.notify_all();
}
debug_printf("job_pool::job_thread: exiting\n");
}
// .TGA image loading
#pragma pack(push)
#pragma pack(1)
struct tga_header
{
uint8_t m_id_len;
uint8_t m_cmap;
uint8_t m_type;
packed_uint<2> m_cmap_first;
packed_uint<2> m_cmap_len;
uint8_t m_cmap_bpp;
packed_uint<2> m_x_org;
packed_uint<2> m_y_org;
packed_uint<2> m_width;
packed_uint<2> m_height;
uint8_t m_depth;
uint8_t m_desc;
};
#pragma pack(pop)
const uint32_t MAX_TGA_IMAGE_SIZE = 16384;
enum tga_image_type
{
cITPalettized = 1,
cITRGB = 2,
cITGrayscale = 3
};
uint8_t *read_tga(const uint8_t *pBuf, uint32_t buf_size, int &width, int &height, int &n_chans)
{
width = 0;
height = 0;
n_chans = 0;
if (buf_size <= sizeof(tga_header))
return nullptr;
const tga_header &hdr = *reinterpret_cast<const tga_header *>(pBuf);
if ((!hdr.m_width) || (!hdr.m_height) || (hdr.m_width > MAX_TGA_IMAGE_SIZE) || (hdr.m_height > MAX_TGA_IMAGE_SIZE))
return nullptr;
if (hdr.m_desc >> 6)
return nullptr;
// Simple validation
if ((hdr.m_cmap != 0) && (hdr.m_cmap != 1))
return nullptr;
if (hdr.m_cmap)
{
if ((hdr.m_cmap_bpp == 0) || (hdr.m_cmap_bpp > 32))
return nullptr;
// Nobody implements CMapFirst correctly, so we're not supporting it. Never seen it used, either.
if (hdr.m_cmap_first != 0)
return nullptr;
}
const bool x_flipped = (hdr.m_desc & 0x10) != 0;
const bool y_flipped = (hdr.m_desc & 0x20) == 0;
bool rle_flag = false;
int file_image_type = hdr.m_type;
if (file_image_type > 8)
{
file_image_type -= 8;
rle_flag = true;
}
const tga_image_type image_type = static_cast<tga_image_type>(file_image_type);
switch (file_image_type)
{
case cITRGB:
if (hdr.m_depth == 8)
return nullptr;
break;
case cITPalettized:
if ((hdr.m_depth != 8) || (hdr.m_cmap != 1) || (hdr.m_cmap_len == 0))
return nullptr;
break;
case cITGrayscale:
if ((hdr.m_cmap != 0) || (hdr.m_cmap_len != 0))
return nullptr;
if ((hdr.m_depth != 8) && (hdr.m_depth != 16))
return nullptr;
break;
default:
return nullptr;
}
uint32_t tga_bytes_per_pixel = 0;
switch (hdr.m_depth)
{
case 32:
tga_bytes_per_pixel = 4;
n_chans = 4;
break;
case 24:
tga_bytes_per_pixel = 3;
n_chans = 3;
break;
case 16:
case 15:
tga_bytes_per_pixel = 2;
// For compatibility with stb_image_write.h
n_chans = ((file_image_type == cITGrayscale) && (hdr.m_depth == 16)) ? 4 : 3;
break;
case 8:
tga_bytes_per_pixel = 1;
// For palettized RGBA support, which both FreeImage and stb_image support.
n_chans = ((file_image_type == cITPalettized) && (hdr.m_cmap_bpp == 32)) ? 4 : 3;
break;
default:
return nullptr;
}
const uint32_t bytes_per_line = hdr.m_width * tga_bytes_per_pixel;
const uint8_t *pSrc = pBuf + sizeof(tga_header);
uint32_t bytes_remaining = buf_size - sizeof(tga_header);
if (hdr.m_id_len)
{
if (bytes_remaining < hdr.m_id_len)
return nullptr;
pSrc += hdr.m_id_len;
bytes_remaining += hdr.m_id_len;
}
color_rgba pal[256];
for (uint32_t i = 0; i < 256; i++)
pal[i].set(0, 0, 0, 255);
if ((hdr.m_cmap) && (hdr.m_cmap_len))
{
if (image_type == cITPalettized)
{
// Note I cannot find any files using 32bpp palettes in the wild (never seen any in ~30 years).
if ( ((hdr.m_cmap_bpp != 32) && (hdr.m_cmap_bpp != 24) && (hdr.m_cmap_bpp != 15) && (hdr.m_cmap_bpp != 16)) || (hdr.m_cmap_len > 256) )
return nullptr;
if (hdr.m_cmap_bpp == 32)
{
const uint32_t pal_size = hdr.m_cmap_len * 4;
if (bytes_remaining < pal_size)
return nullptr;
for (uint32_t i = 0; i < hdr.m_cmap_len; i++)
{
pal[i].r = pSrc[i * 4 + 2];
pal[i].g = pSrc[i * 4 + 1];
pal[i].b = pSrc[i * 4 + 0];
pal[i].a = pSrc[i * 4 + 3];
}
bytes_remaining -= pal_size;
pSrc += pal_size;
}
else if (hdr.m_cmap_bpp == 24)
{
const uint32_t pal_size = hdr.m_cmap_len * 3;
if (bytes_remaining < pal_size)
return nullptr;
for (uint32_t i = 0; i < hdr.m_cmap_len; i++)
{
pal[i].r = pSrc[i * 3 + 2];
pal[i].g = pSrc[i * 3 + 1];
pal[i].b = pSrc[i * 3 + 0];
pal[i].a = 255;
}
bytes_remaining -= pal_size;
pSrc += pal_size;
}
else
{
const uint32_t pal_size = hdr.m_cmap_len * 2;
if (bytes_remaining < pal_size)
return nullptr;
for (uint32_t i = 0; i < hdr.m_cmap_len; i++)
{
const uint32_t v = pSrc[i * 2 + 0] | (pSrc[i * 2 + 1] << 8);
pal[i].r = (((v >> 10) & 31) * 255 + 15) / 31;
pal[i].g = (((v >> 5) & 31) * 255 + 15) / 31;
pal[i].b = ((v & 31) * 255 + 15) / 31;
pal[i].a = 255;
}
bytes_remaining -= pal_size;
pSrc += pal_size;
}
}
else
{
const uint32_t bytes_to_skip = (hdr.m_cmap_bpp >> 3) * hdr.m_cmap_len;
if (bytes_remaining < bytes_to_skip)
return nullptr;
pSrc += bytes_to_skip;
bytes_remaining += bytes_to_skip;
}
}
width = hdr.m_width;
height = hdr.m_height;
const uint32_t source_pitch = width * tga_bytes_per_pixel;
const uint32_t dest_pitch = width * n_chans;
uint8_t *pImage = (uint8_t *)malloc(dest_pitch * height);
if (!pImage)
return nullptr;
std::vector<uint8_t> input_line_buf;
if (rle_flag)
input_line_buf.resize(source_pitch);
int run_type = 0, run_remaining = 0;
uint8_t run_pixel[4];
memset(run_pixel, 0, sizeof(run_pixel));
for (int y = 0; y < height; y++)
{
const uint8_t *pLine_data;
if (rle_flag)
{
int pixels_remaining = width;
uint8_t *pDst = &input_line_buf[0];
do
{
if (!run_remaining)
{
if (bytes_remaining < 1)
{
free(pImage);
return nullptr;
}
int v = *pSrc++;
bytes_remaining--;
run_type = v & 0x80;
run_remaining = (v & 0x7F) + 1;
if (run_type)
{
if (bytes_remaining < tga_bytes_per_pixel)
{
free(pImage);
return nullptr;
}
memcpy(run_pixel, pSrc, tga_bytes_per_pixel);
pSrc += tga_bytes_per_pixel;
bytes_remaining -= tga_bytes_per_pixel;
}
}
const uint32_t n = std::min<uint32_t>(pixels_remaining, run_remaining);
pixels_remaining -= n;
run_remaining -= n;
if (run_type)
{
for (uint32_t i = 0; i < n; i++)
for (uint32_t j = 0; j < tga_bytes_per_pixel; j++)
*pDst++ = run_pixel[j];
}
else
{
const uint32_t bytes_wanted = n * tga_bytes_per_pixel;
if (bytes_remaining < bytes_wanted)
{
free(pImage);
return nullptr;
}
memcpy(pDst, pSrc, bytes_wanted);
pDst += bytes_wanted;
pSrc += bytes_wanted;
bytes_remaining -= bytes_wanted;
}
} while (pixels_remaining);
assert((pDst - &input_line_buf[0]) == width * tga_bytes_per_pixel);
pLine_data = &input_line_buf[0];
}
else
{
if (bytes_remaining < source_pitch)
{
free(pImage);
return nullptr;
}
pLine_data = pSrc;
bytes_remaining -= source_pitch;
pSrc += source_pitch;
}
// Convert to 24bpp RGB or 32bpp RGBA.
uint8_t *pDst = pImage + (y_flipped ? (height - 1 - y) : y) * dest_pitch + (x_flipped ? (width - 1) * n_chans : 0);
const int dst_stride = x_flipped ? -((int)n_chans) : n_chans;
switch (hdr.m_depth)
{
case 32:
assert(tga_bytes_per_pixel == 4 && n_chans == 4);
for (int i = 0; i < width; i++, pLine_data += 4, pDst += dst_stride)
{
pDst[0] = pLine_data[2];
pDst[1] = pLine_data[1];
pDst[2] = pLine_data[0];
pDst[3] = pLine_data[3];
}
break;
case 24:
assert(tga_bytes_per_pixel == 3 && n_chans == 3);
for (int i = 0; i < width; i++, pLine_data += 3, pDst += dst_stride)
{
pDst[0] = pLine_data[2];
pDst[1] = pLine_data[1];
pDst[2] = pLine_data[0];
}
break;
case 16:
case 15:
if (image_type == cITRGB)
{
assert(tga_bytes_per_pixel == 2 && n_chans == 3);
for (int i = 0; i < width; i++, pLine_data += 2, pDst += dst_stride)
{
const uint32_t v = pLine_data[0] | (pLine_data[1] << 8);
pDst[0] = (((v >> 10) & 31) * 255 + 15) / 31;
pDst[1] = (((v >> 5) & 31) * 255 + 15) / 31;
pDst[2] = ((v & 31) * 255 + 15) / 31;
}
}
else
{
assert(image_type == cITGrayscale && tga_bytes_per_pixel == 2 && n_chans == 4);
for (int i = 0; i < width; i++, pLine_data += 2, pDst += dst_stride)
{
pDst[0] = pLine_data[0];
pDst[1] = pLine_data[0];
pDst[2] = pLine_data[0];
pDst[3] = pLine_data[1];
}
}
break;
case 8:
assert(tga_bytes_per_pixel == 1);
if (image_type == cITPalettized)
{
if (hdr.m_cmap_bpp == 32)
{
assert(n_chans == 4);
for (int i = 0; i < width; i++, pLine_data++, pDst += dst_stride)
{
const uint32_t c = *pLine_data;
pDst[0] = pal[c].r;
pDst[1] = pal[c].g;
pDst[2] = pal[c].b;
pDst[3] = pal[c].a;
}
}
else
{
assert(n_chans == 3);
for (int i = 0; i < width; i++, pLine_data++, pDst += dst_stride)
{
const uint32_t c = *pLine_data;
pDst[0] = pal[c].r;
pDst[1] = pal[c].g;
pDst[2] = pal[c].b;
}
}
}
else
{
assert(n_chans == 3);
for (int i = 0; i < width; i++, pLine_data++, pDst += dst_stride)
{
const uint8_t c = *pLine_data;
pDst[0] = c;
pDst[1] = c;
pDst[2] = c;
}
}
break;
default:
assert(0);
break;
}
} // y
return pImage;
}
uint8_t *read_tga(const char *pFilename, int &width, int &height, int &n_chans)
{
width = height = n_chans = 0;
uint8_vec filedata;
if (!read_file_to_vec(pFilename, filedata))
return nullptr;
if (!filedata.size() || (filedata.size() > UINT32_MAX))
return nullptr;
return read_tga(&filedata[0], (uint32_t)filedata.size(), width, height, n_chans);
}
} // namespace basisu