int32_t dt_control_merge_hdr_job_run(dt_job_t *job)
{
long int imgid = -1;
dt_control_image_enumerator_t *t1 = (dt_control_image_enumerator_t *)job->param;
GList *t = t1->index;
int total = g_list_length(t);
char message[512]= {0};
double fraction=0;
snprintf(message, 512, ngettext ("merging %d image", "merging %d images", total), total );
const guint *jid = dt_control_backgroundjobs_create(darktable.control, 1, message);
float *pixels = NULL;
float *weight = NULL;
int wd = 0, ht = 0, first_imgid = -1;
uint32_t filter = 0;
float whitelevel = 0.0f;
total ++;
while(t)
{
imgid = (long int)t->data;
dt_mipmap_buffer_t buf;
dt_mipmap_cache_read_get(darktable.mipmap_cache, &buf, imgid, DT_MIPMAP_FULL, DT_MIPMAP_BLOCKING);
// just take a copy. also do it after blocking read, so filters and bpp will make sense.
const dt_image_t *img = dt_image_cache_read_get(darktable.image_cache, imgid);
dt_image_t image = *img;
dt_image_cache_read_release(darktable.image_cache, img);
if(image.filters == 0 || image.bpp != sizeof(uint16_t))
{
dt_control_log(_("exposure bracketing only works on raw images"));
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
free(pixels);
free(weight);
goto error;
}
filter = dt_image_flipped_filter(img);
if(buf.size != DT_MIPMAP_FULL)
{
dt_control_log(_("failed to get raw buffer from image `%s'"), image.filename);
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
free(pixels);
free(weight);
goto error;
}
if(!pixels)
{
first_imgid = imgid;
pixels = (float *)malloc(sizeof(float)*image.width*image.height);
weight = (float *)malloc(sizeof(float)*image.width*image.height);
memset(pixels, 0x0, sizeof(float)*image.width*image.height);
memset(weight, 0x0, sizeof(float)*image.width*image.height);
wd = image.width;
ht = image.height;
}
else if(image.width != wd || image.height != ht)
{
dt_control_log(_("images have to be of same size!"));
free(pixels);
free(weight);
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
goto error;
}
// if no valid exif data can be found, assume peleng fisheye at f/16, 8mm, with half of the light lost in the system => f/22
const float eap = image.exif_aperture > 0.0f ? image.exif_aperture : 22.0f;
const float efl = image.exif_focal_length > 0.0f ? image.exif_focal_length : 8.0f;
const float rad = .5f * efl/eap;
const float aperture = M_PI * rad * rad;
const float iso = image.exif_iso > 0.0f ? image.exif_iso : 100.0f;
const float exp = image.exif_exposure > 0.0f ? image.exif_exposure : 1.0f;
const float cal = 100.0f/(aperture*exp*iso);
// about proportional to how many photons we can expect from this shot:
const float photoncnt = 100.0f*aperture*exp/iso;
// stupid, but we don't know the real sensor saturation level:
uint16_t saturation = 0;
for(int k=0; k<wd*ht; k++)
saturation = MAX(saturation, ((uint16_t *)buf.buf)[k]);
// seems to be around 64500--64700 for 5dm2
// fprintf(stderr, "saturation: %u\n", saturation);
whitelevel = fmaxf(whitelevel, saturation*cal);
#ifdef _OPENMP
#pragma omp parallel for schedule(static) default(none) shared(buf, pixels, weight, wd, ht, saturation)
#endif
for(int k=0; k<wd*ht; k++)
{
const uint16_t in = ((uint16_t *)buf.buf)[k];
// weights based on siggraph 12 poster
// zijian zhu, zhengguo li, susanto rahardja, pasi fraenti
// 2d denoising factor for high dynamic range imaging
float w = envelope(in/(float)saturation) * photoncnt;
// in case we are black and drop to zero weight, give it something
// just so numerics don't collapse. blown out whites are handled below.
if(w < 1e-3f && in < saturation/3) w = 1e-3f;
pixels[k] += w * in * cal;
weight[k] += w;
}
t = g_list_delete_link(t, t);
/* update backgroundjob ui plate */
fraction+=1.0/total;
dt_control_backgroundjobs_progress(darktable.control, jid, fraction);
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
}
// normalize by white level to make clipping at 1.0 work as expected (to be sure, scale down one more stop, thus the 0.5):
#ifdef _OPENMP
#pragma omp parallel for schedule(static) default(none) shared(pixels, wd, ht, weight, whitelevel)
#endif
for(int k=0; k<wd*ht; k++)
{
// in case w == 0, all pixels were overexposed (too dark would have been clamped to w >= eps above)
if(weight[k] < 1e-3f)
pixels[k] = 1.f; // mark as blown out.
else // normalize:
pixels[k] = fmaxf(0.0f, pixels[k]/(whitelevel*weight[k]));
}
// output hdr as digital negative with exif data.
uint8_t exif[65535];
char pathname[DT_MAX_PATH_LEN];
dt_image_full_path(first_imgid, pathname, DT_MAX_PATH_LEN);
// last param is dng mode
const int exif_len = dt_exif_read_blob(exif, pathname, first_imgid, 0, wd, ht, 1);
char *c = pathname + strlen(pathname);
while(*c != '.' && c > pathname) c--;
g_strlcpy(c, "-hdr.dng", sizeof(pathname)-(c-pathname));
dt_imageio_write_dng(pathname, pixels, wd, ht, exif, exif_len, filter, 1.0f);
dt_control_backgroundjobs_progress(darktable.control, jid, 1.0f);
while(*c != '/' && c > pathname) c--;
dt_control_log(_("wrote merged hdr `%s'"), c+1);
// import new image
gchar *directory = g_path_get_dirname((const gchar *)pathname);
dt_film_t film;
const int filmid = dt_film_new(&film, directory);
dt_image_import(filmid, pathname, TRUE);
g_free (directory);
free(pixels);
free(weight);
error:
dt_control_backgroundjobs_destroy(darktable.control, jid);
dt_control_queue_redraw_center();
return 0;
}
int32_t dt_control_merge_hdr_job_run(dt_job_t *job)
{
long int imgid = -1;
dt_control_image_enumerator_t *t1 = (dt_control_image_enumerator_t *)job->param;
GList *t = t1->index;
int total = g_list_length(t);
char message[512]= {0};
double fraction=0;
snprintf(message, 512, ngettext ("merging %d image", "merging %d images", total), total );
const guint *jid = dt_control_backgroundjobs_create(darktable.control, 1, message);
float *pixels = NULL;
float *weight = NULL;
int wd = 0, ht = 0, first_imgid = -1;
uint32_t filter = 0;
float whitelevel = 0.0f;
total ++;
while(t)
{
imgid = (long int)t->data;
dt_mipmap_buffer_t buf;
dt_mipmap_cache_read_get(darktable.mipmap_cache, &buf, imgid, DT_MIPMAP_FULL, DT_MIPMAP_BLOCKING);
// just take a copy. also do it after blocking read, so filters and bpp will make sense.
const dt_image_t *img = dt_image_cache_read_get(darktable.image_cache, imgid);
dt_image_t image = *img;
dt_image_cache_read_release(darktable.image_cache, img);
if(image.filters == 0 || image.bpp != sizeof(uint16_t))
{
dt_control_log(_("exposure bracketing only works on raw images"));
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
free(pixels);
free(weight);
goto error;
}
filter = dt_image_flipped_filter(img);
if(buf.size != DT_MIPMAP_FULL)
{
dt_control_log(_("failed to get raw buffer from image `%s'"), image.filename);
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
free(pixels);
free(weight);
goto error;
}
if(!pixels)
{
first_imgid = imgid;
pixels = (float *)malloc(sizeof(float)*image.width*image.height);
weight = (float *)malloc(sizeof(float)*image.width*image.height);
memset(pixels, 0x0, sizeof(float)*image.width*image.height);
memset(weight, 0x0, sizeof(float)*image.width*image.height);
wd = image.width;
ht = image.height;
}
else if(image.width != wd || image.height != ht)
{
dt_control_log(_("images have to be of same size!"));
free(pixels);
free(weight);
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
goto error;
}
// if no valid exif data can be found, assume peleng fisheye at f/16, 8mm, with half of the light lost in the system => f/22
const float eap = image.exif_aperture > 0.0f ? image.exif_aperture : 22.0f;
const float efl = image.exif_focal_length > 0.0f ? image.exif_focal_length : 8.0f;
const float rad = .5f * efl/eap;
const float aperture = M_PI * rad * rad;
const float iso = image.exif_iso > 0.0f ? image.exif_iso : 100.0f;
const float exp = image.exif_exposure > 0.0f ? image.exif_exposure : 1.0f;
const float cal = 100.0f/(aperture*exp*iso);
whitelevel = fmaxf(whitelevel, cal);
#ifdef _OPENMP
#pragma omp parallel for schedule(static) default(none) shared(buf, pixels, weight, wd, ht)
#endif
for(int k=0; k<wd*ht; k++)
{
const uint16_t in = ((uint16_t *)buf.buf)[k];
const float w = .001f + (in >= 1000 ? (in < 65000 ? in/65000.0f : 0.0f) : exp * 0.01f);
pixels[k] += w * in * cal;
weight[k] += w;
}
t = g_list_delete_link(t, t);
/* update backgroundjob ui plate */
fraction+=1.0/total;
dt_control_backgroundjobs_progress(darktable.control, jid, fraction);
dt_mipmap_cache_read_release(darktable.mipmap_cache, &buf);
}
// normalize by white level to make clipping at 1.0 work as expected (to be sure, scale down one more stop, thus the 0.5):
#ifdef _OPENMP
#pragma omp parallel for schedule(static) default(none) shared(pixels, wd, ht, weight, whitelevel)
#endif
for(int k=0; k<wd*ht; k++) pixels[k] = fmaxf(0.0f, fminf(2.0f, pixels[k]/((.5f*whitelevel*65535.0f)*weight[k])));
// output hdr as digital negative with exif data.
uint8_t exif[65535];
char pathname[1024];
dt_image_full_path(first_imgid, pathname, 1024);
const int exif_len = dt_exif_read_blob(exif, pathname, 0, first_imgid);
char *c = pathname + strlen(pathname);
while(*c != '.' && c > pathname) c--;
g_strlcpy(c, "-hdr.dng", sizeof(pathname)-(c-pathname));
dt_imageio_write_dng(pathname, pixels, wd, ht, exif, exif_len, filter, whitelevel);
dt_control_backgroundjobs_progress(darktable.control, jid, 1.0f);
while(*c != '/' && c > pathname) c--;
dt_control_log(_("wrote merged hdr `%s'"), c+1);
// import new image
gchar *directory = g_path_get_dirname((const gchar *)pathname);
dt_film_t film;
const int filmid = dt_film_new(&film, directory);
dt_image_import(filmid, pathname, TRUE);
g_free (directory);
free(pixels);
free(weight);
error:
dt_control_backgroundjobs_destroy(darktable.control, jid);
return 0;
}
