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#include <mupdf/fitz.h>
typedef struct fz_test_device_s
{
fz_device super;
int *is_color;
float threshold;
} fz_test_device;
static int
is_rgb_color(float threshold, float r, float g, float b)
{
float rg_diff = fz_abs(r - g);
float rb_diff = fz_abs(r - b);
float gb_diff = fz_abs(g - b);
return rg_diff > threshold || rb_diff > threshold || gb_diff > threshold;
}
static int
is_rgb_color_u8(int threshold_u8, int r, int g, int b)
{
int rg_diff = fz_absi(r - g);
int rb_diff = fz_absi(r - b);
int gb_diff = fz_absi(g - b);
return rg_diff > threshold_u8 || rb_diff > threshold_u8 || gb_diff > threshold_u8;
}
static void
fz_test_color(fz_context *ctx, fz_device *dev, fz_colorspace *colorspace, const float *color)
{
fz_test_device *t = (fz_test_device*)dev;
if (!*t->is_color && colorspace && colorspace != fz_device_gray(ctx))
{
if (colorspace == fz_device_rgb(ctx))
{
if (is_rgb_color(t->threshold, color[0], color[1], color[2]))
{
*t->is_color = 1;
dev->hints |= FZ_IGNORE_IMAGE;
fz_throw(ctx, FZ_ERROR_ABORT, "Page found as color; stopping interpretation");
}
}
else
{
float rgb[3];
fz_convert_color(ctx, fz_device_rgb(ctx), rgb, colorspace, color);
if (is_rgb_color(t->threshold, rgb[0], rgb[1], rgb[2]))
{
*t->is_color = 1;
dev->hints |= FZ_IGNORE_IMAGE;
fz_throw(ctx, FZ_ERROR_ABORT, "Page found as color; stopping interpretation");
}
}
}
}
static void
fz_test_fill_path(fz_context *ctx, fz_device *dev, fz_path *path, int even_odd, const fz_matrix *ctm,
fz_colorspace *colorspace, float *color, float alpha)
{
if (alpha != 0.0f)
fz_test_color(ctx, dev, colorspace, color);
}
static void
fz_test_stroke_path(fz_context *ctx, fz_device *dev, fz_path *path, fz_stroke_state *stroke,
const fz_matrix *ctm, fz_colorspace *colorspace, float *color, float alpha)
{
if (alpha != 0.0f)
fz_test_color(ctx, dev, colorspace, color);
}
static void
fz_test_fill_text(fz_context *ctx, fz_device *dev, fz_text *text, const fz_matrix *ctm,
fz_colorspace *colorspace, float *color, float alpha)
{
if (alpha != 0.0f)
fz_test_color(ctx, dev, colorspace, color);
}
static void
fz_test_stroke_text(fz_context *ctx, fz_device *dev, fz_text *text, fz_stroke_state *stroke,
const fz_matrix *ctm, fz_colorspace *colorspace, float *color, float alpha)
{
if (alpha != 0.0f)
fz_test_color(ctx, dev, colorspace, color);
}
struct shadearg
{
fz_device *dev;
fz_shade *shade;
};
static void
prepare_vertex(fz_context *ctx, void *arg_, fz_vertex *v, const float *color)
{
struct shadearg *arg = arg_;
fz_device *dev = arg->dev;
fz_shade *shade = arg->shade;
if (!shade->use_function)
fz_test_color(ctx, dev, shade->colorspace, color);
}
static void
fz_test_fill_shade(fz_context *ctx, fz_device *dev, fz_shade *shade, const fz_matrix *ctm, float alpha)
{
if (shade->use_function)
{
int i;
for (i = 0; i < 256; i++)
fz_test_color(ctx, dev, shade->colorspace, shade->function[i]);
}
else
{
struct shadearg arg;
arg.dev = dev;
arg.shade = shade;
fz_process_mesh(ctx, shade, ctm, prepare_vertex, NULL, &arg);
}
}
static void
fz_test_fill_image(fz_context *ctx, fz_device *dev, fz_image *image, const fz_matrix *ctm, float alpha)
{
fz_test_device *t = (fz_test_device*)dev;
fz_pixmap *pix;
unsigned int count, i, k;
unsigned char *s;
if (*t->is_color || !image->colorspace || image->colorspace == fz_device_gray(ctx))
return;
if (image->buffer && image->bpc == 8)
{
fz_stream *stream = fz_open_compressed_buffer(ctx, image->buffer);
count = (unsigned int)image->w * (unsigned int)image->h;
if (image->colorspace == fz_device_rgb(ctx))
{
int threshold_u8 = t->threshold * 255;
for (i = 0; i < count; i++)
{
int r = fz_read_byte(ctx, stream);
int g = fz_read_byte(ctx, stream);
int b = fz_read_byte(ctx, stream);
if (is_rgb_color_u8(threshold_u8, r, g, b))
{
*t->is_color = 1;
dev->hints |= FZ_IGNORE_IMAGE;
fz_drop_stream(ctx, stream);
fz_throw(ctx, FZ_ERROR_ABORT, "Page found as color; stopping interpretation");
break;
}
}
}
else
{
fz_color_converter cc;
unsigned int n = (unsigned int)image->n;
fz_init_cached_color_converter(ctx, &cc, fz_device_rgb(ctx), image->colorspace);
for (i = 0; i < count; i++)
{
float cs[FZ_MAX_COLORS];
float ds[FZ_MAX_COLORS];
for (k = 0; k < n; k++)
cs[k] = fz_read_byte(ctx, stream) / 255.0f;
cc.convert(ctx, &cc, ds, cs);
if (is_rgb_color(t->threshold, ds[0], ds[1], ds[2]))
{
*t->is_color = 1;
dev->hints |= FZ_IGNORE_IMAGE;
break;
}
}
fz_fin_cached_color_converter(ctx, &cc);
}
fz_drop_stream(ctx, stream);
return;
}
pix = fz_new_pixmap_from_image(ctx, image, 0, 0);
if (pix == NULL) /* Should never happen really, but... */
return;
count = (unsigned int)pix->w * (unsigned int)pix->h;
s = pix->samples;
if (pix->colorspace == fz_device_rgb(ctx))
{
int threshold_u8 = t->threshold * 255;
for (i = 0; i < count; i++)
{
if (s[3] != 0 && is_rgb_color_u8(threshold_u8, s[0], s[1], s[2]))
{
*t->is_color = 1;
dev->hints |= FZ_IGNORE_IMAGE;
fz_drop_pixmap(ctx, pix);
fz_throw(ctx, FZ_ERROR_ABORT, "Page found as color; stopping interpretation");
break;
}
s += 4;
}
}
else
{
fz_color_converter cc;
unsigned int n = (unsigned int)pix->n-1;
fz_init_cached_color_converter(ctx, &cc, fz_device_rgb(ctx), pix->colorspace);
for (i = 0; i < count; i++)
{
float cs[FZ_MAX_COLORS];
float ds[FZ_MAX_COLORS];
for (k = 0; k < n; k++)
cs[k] = (*s++) / 255.0f;
if (*s++ == 0)
continue;
cc.convert(ctx, &cc, ds, cs);
if (is_rgb_color(t->threshold, ds[0], ds[1], ds[2]))
{
*t->is_color = 1;
dev->hints |= FZ_IGNORE_IMAGE;
fz_drop_pixmap(ctx, pix);
fz_throw(ctx, FZ_ERROR_ABORT, "Page found as color; stopping interpretation");
break;
}
}
fz_fin_cached_color_converter(ctx, &cc);
}
fz_drop_pixmap(ctx, pix);
}
static void
fz_test_fill_image_mask(fz_context *ctx, fz_device *dev, fz_image *image, const fz_matrix *ctm,
fz_colorspace *colorspace, float *color, float alpha)
{
/* We assume that at least some of the image pixels are non-zero */
fz_test_color(ctx, dev, colorspace, color);
}
fz_device *
fz_new_test_device(fz_context *ctx, int *is_color, float threshold)
{
fz_test_device *dev = fz_new_device(ctx, sizeof *dev);
dev->super.fill_path = fz_test_fill_path;
dev->super.stroke_path = fz_test_stroke_path;
dev->super.fill_text = fz_test_fill_text;
dev->super.stroke_text = fz_test_stroke_text;
dev->super.fill_shade = fz_test_fill_shade;
dev->super.fill_image = fz_test_fill_image;
dev->super.fill_image_mask = fz_test_fill_image_mask;
dev->is_color = is_color;
dev->threshold = threshold;
*dev->is_color = 0;
return (fz_device*)dev;
}
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