Skip to content

[imageio] Radically speed up PFM loading #17689

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
Oct 19, 2024
Merged

[imageio] Radically speed up PFM loading #17689

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
459d0c9
Redesign load loops to make them OpenMP compatible
victoryforce Oct 17, 2024
1255ed7
Add OpenMP parallelization to PFM data load loops
victoryforce Oct 18, 2024
4e64675
Get rid of the additional loop of reversing the order of rows
victoryforce Oct 18, 2024
31b102f
Minor code reformatting
victoryforce Oct 18, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
90 changes: 58 additions & 32 deletions src/imageio/imageio_pfm.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -34,21 +34,32 @@
#include <time.h>
#include <unistd.h>

dt_imageio_retval_t dt_imageio_open_pfm(dt_image_t *img, const char *filename, dt_mipmap_buffer_t *mbuf)
dt_imageio_retval_t dt_imageio_open_pfm(dt_image_t *img,
const char *filename,
dt_mipmap_buffer_t *mbuf)
{
const char *ext = filename + strlen(filename);
while(*ext != '.' && ext > filename) ext--;
if(strcasecmp(ext, ".pfm")) return DT_IMAGEIO_LOAD_FAILED;

while(*ext != '.' && ext > filename)
ext--;

if(strcasecmp(ext, ".pfm"))
return DT_IMAGEIO_LOAD_FAILED;

FILE *f = g_fopen(filename, "rb");
if(!f) return DT_IMAGEIO_FILE_NOT_FOUND;
if(!f)
return DT_IMAGEIO_FILE_NOT_FOUND;

int ret = 0;
int cols = 3;
float scale_factor;
char head[2] = { 'X', 'X' };

ret = fscanf(f, "%c%c\n", head, head + 1);
if(ret != 2 || head[0] != 'P') goto error_corrupt;

if(ret != 2 || head[0] != 'P')
goto error_corrupt;

if(head[1] == 'F')
cols = 3;
else if(head[1] == 'f')
Expand All @@ -59,63 +70,78 @@ dt_imageio_retval_t dt_imageio_open_pfm(dt_image_t *img, const char *filename, d
char width_string[10] = { 0 };
char height_string[10] = { 0 };
char scale_factor_string[64] = { 0 };

ret = fscanf(f, "%9s %9s %63s%*[^\n]", width_string, height_string, scale_factor_string);
if(ret != 3) goto error_corrupt;

if(ret != 3)
goto error_corrupt;

errno = 0;
img->width = strtol(width_string, NULL, 0);
img->height = strtol(height_string, NULL, 0);
scale_factor = g_ascii_strtod(scale_factor_string, NULL);
if(errno != 0) goto error_corrupt;
if(img->width <= 0 || img->height <= 0 ) goto error_corrupt;

if(errno != 0)
goto error_corrupt;
if(img->width <= 0 || img->height <= 0 )
goto error_corrupt;

ret = fread(&ret, sizeof(char), 1, f);
if(ret != 1) goto error_corrupt;
if(ret != 1)
goto error_corrupt;
ret = 0;

int swap_byte_order = (scale_factor >= 0.0) ^ (G_BYTE_ORDER == G_BIG_ENDIAN);

img->buf_dsc.channels = 4;
img->buf_dsc.datatype = TYPE_FLOAT;
float *buf = (float *)dt_mipmap_cache_alloc(mbuf, img);
if(!buf) goto error_cache_full;
if(!buf)
goto error_cache_full;

const size_t npixels = (size_t)img->width * img->height;

float *readbuf = dt_alloc_align_float(npixels * 4);
if(!readbuf)
goto error_cache_full;

union { float f; guint32 i; } value;

if(cols == 3)
{
ret = fread(buf, 3 * sizeof(float), (size_t)img->width * img->height, f);
for(size_t i = (size_t)img->width * img->height; i > 0; i--)
for(int c = 0; c < 3; c++)
ret = fread(readbuf, 3 * sizeof(float), npixels, f);

DT_OMP_FOR(collapse(2))
for(size_t j = 0; j < img->height; j++)
for(size_t i = 0; i < img->width; i++)
{
union { float f; guint32 i; } v;
v.f = buf[3 * (i - 1) + c];
if(swap_byte_order) v.i = GUINT32_SWAP_LE_BE(v.i);
buf[4 * (i - 1) + c] = v.f;
dt_aligned_pixel_t pix = {0.0f, 0.0f, 0.0f, 0.0f};
for_three_channels(c)
{
value.f = readbuf[3 * ((img->height - 1 - j) * img->width + i) + c];
if(swap_byte_order) value.i = GUINT32_SWAP_LE_BE(value.i);
pix[c] = value.f;
}
copy_pixel_nontemporal(&buf[4 * (img->width * j + i)], pix);
}
}
else
{
ret = fread(readbuf, sizeof(float), npixels, f);

DT_OMP_FOR(collapse(2))
for(size_t j = 0; j < img->height; j++)
for(size_t i = 0; i < img->width; i++)
{
union { float f; guint32 i; } v;
ret = fread(&v.f, sizeof(float), 1, f);
if(swap_byte_order) v.i = GUINT32_SWAP_LE_BE(v.i);
value.f = readbuf[((img->height - 1 - j) * img->width + i)];
if(swap_byte_order) value.i = GUINT32_SWAP_LE_BE(value.i);
buf[4 * (img->width * j + i) + 2] = buf[4 * (img->width * j + i) + 1]
= buf[4 * (img->width * j + i) + 0] = v.f;
= buf[4 * (img->width * j + i) + 0] = value.f;
}

float *line = (float *)calloc(4 * img->width, sizeof(float));
if(line == NULL) goto error_cache_full;

for(size_t j = 0; j < img->height / 2; j++)
{
memcpy(line, buf + img->width * j * 4, sizeof(float) * 4 * img->width);
memcpy(buf + img->width * j * 4, buf + img->width * (img->height - 1 - j) * 4,
sizeof(float) * 4 * img->width);
memcpy(buf + img->width * (img->height - 1 - j) * 4, line, sizeof(float) * 4 * img->width);
}

free(line);
fclose(f);
dt_free_align(readbuf);

img->buf_dsc.cst = IOP_CS_RGB;
img->buf_dsc.filters = 0u;
Expand Down
Loading