eBookReaderSwitch/mupdf/source/fitz/output-pnm.c

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#include "mupdf/fitz.h"
/*
* Write pixmap to PNM file (without alpha channel)
*/
static void
pnm_write_header(fz_context *ctx, fz_band_writer *writer, fz_colorspace *cs)
{
fz_output *out = writer->out;
int w = writer->w;
int h = writer->h;
int n = writer->n;
int alpha = writer->alpha;
if (writer->s != 0)
fz_throw(ctx, FZ_ERROR_GENERIC, "PNM writer cannot cope with spot colors");
if (alpha)
fz_throw(ctx, FZ_ERROR_GENERIC, "PNM writer cannot cope with alpha");
n -= alpha;
if (n != 1 && n != 3)
fz_throw(ctx, FZ_ERROR_GENERIC, "pixmap must be grayscale or rgb to write as pnm");
if (n == 1)
fz_write_printf(ctx, out, "P5\n");
if (n == 3)
fz_write_printf(ctx, out, "P6\n");
fz_write_printf(ctx, out, "%d %d\n", w, h);
fz_write_printf(ctx, out, "255\n");
}
static void
pnm_write_band(fz_context *ctx, fz_band_writer *writer, int stride, int band_start, int band_height, const unsigned char *p)
{
fz_output *out = writer->out;
int w = writer->w;
int h = writer->h;
int n = writer->n;
int len;
int end = band_start + band_height;
if (n != 1 && n != 3)
fz_throw(ctx, FZ_ERROR_GENERIC, "pixmap must be grayscale or rgb to write as pnm");
if (!out)
return;
if (end > h)
end = h;
end -= band_start;
/* Tests show that writing single bytes out at a time
* is appallingly slow. We get a huge improvement
* by collating stuff into buffers first. */
while (end--)
{
len = w;
while (len)
{
int num_written = len;
switch (n)
{
case 1:
/* No collation required */
fz_write_data(ctx, out, p, num_written);
p += num_written;
break;
case 3:
fz_write_data(ctx, out, p, num_written*3);
p += num_written*3;
break;
}
len -= num_written;
}
p += stride - w*n;
}
}
fz_band_writer *fz_new_pnm_band_writer(fz_context *ctx, fz_output *out)
{
fz_band_writer *writer = fz_new_band_writer(ctx, fz_band_writer, out);
writer->header = pnm_write_header;
writer->band = pnm_write_band;
return writer;
}
void
fz_write_pixmap_as_pnm(fz_context *ctx, fz_output *out, fz_pixmap *pixmap)
{
fz_band_writer *writer = fz_new_pnm_band_writer(ctx, out);
fz_try(ctx)
{
fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, 0, 0, 0, pixmap->colorspace, pixmap->seps);
fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);
}
fz_always(ctx)
fz_drop_band_writer(ctx, writer);
fz_catch(ctx)
fz_rethrow(ctx);
}
void
fz_save_pixmap_as_pnm(fz_context *ctx, fz_pixmap *pixmap, const char *filename)
{
fz_band_writer *writer = NULL;
fz_output *out = fz_new_output_with_path(ctx, filename, 0);
fz_var(writer);
fz_try(ctx)
{
writer = fz_new_pnm_band_writer(ctx, out);
fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, 0, 0, 0, pixmap->colorspace, pixmap->seps);
fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);
fz_close_output(ctx, out);
}
fz_always(ctx)
{
fz_drop_band_writer(ctx, writer);
fz_drop_output(ctx, out);
}
fz_catch(ctx)
fz_rethrow(ctx);
}
/*
* Write pixmap to PAM file (with or without alpha channel)
*/
static void
pam_write_header(fz_context *ctx, fz_band_writer *writer, fz_colorspace *cs)
{
fz_output *out = writer->out;
int w = writer->w;
int h = writer->h;
int n = writer->n;
int alpha = writer->alpha;
if (writer->s != 0)
fz_throw(ctx, FZ_ERROR_GENERIC, "PAM writer cannot cope with spot colors");
fz_write_printf(ctx, out, "P7\n");
fz_write_printf(ctx, out, "WIDTH %d\n", w);
fz_write_printf(ctx, out, "HEIGHT %d\n", h);
fz_write_printf(ctx, out, "DEPTH %d\n", n);
fz_write_printf(ctx, out, "MAXVAL 255\n");
n -= alpha;
if (n == 0 && alpha) fz_write_printf(ctx, out, "TUPLTYPE GRAYSCALE\n");
else if (n == 1 && !alpha) fz_write_printf(ctx, out, "TUPLTYPE GRAYSCALE\n");
else if (n == 1 && alpha) fz_write_printf(ctx, out, "TUPLTYPE GRAYSCALE_ALPHA\n");
else if (n == 3 && !alpha) fz_write_printf(ctx, out, "TUPLTYPE RGB\n");
else if (n == 3 && alpha) fz_write_printf(ctx, out, "TUPLTYPE RGB_ALPHA\n");
else if (n == 4 && !alpha) fz_write_printf(ctx, out, "TUPLTYPE CMYK\n");
else if (n == 4 && alpha) fz_write_printf(ctx, out, "TUPLTYPE CMYK_ALPHA\n");
fz_write_printf(ctx, out, "ENDHDR\n");
}
static void
pam_write_band(fz_context *ctx, fz_band_writer *writer, int stride, int band_start, int band_height, const unsigned char *sp)
{
fz_output *out = writer->out;
int w = writer->w;
int h = writer->h;
int n = writer->n;
int alpha = writer->alpha;
int x, y;
int end = band_start + band_height;
if (!out)
return;
if (end > h)
end = h;
end -= band_start;
if (alpha)
{
/* Buffer must be a multiple of 2, 3 and 5 at least. */
/* Also, for the generic case, it must be bigger than FZ_MAX_COLORS */
char buffer[2*3*4*5*6];
char *b = buffer;
stride -= n * w;
switch (n)
{
case 2:
for (y = 0; y < end; y++)
{
for (x = 0; x < w; x++)
{
int a = sp[1];
*b++ = a ? (sp[0] * 255 + (a>>1))/a : 0;
*b++ = a;
sp += 2;
if (b == &buffer[sizeof(buffer)])
{
fz_write_data(ctx, out, buffer, sizeof(buffer));
b = buffer;
}
}
sp += stride;
}
if (b != buffer)
fz_write_data(ctx, out, buffer, b - buffer);
break;
case 4:
for (y = 0; y < end; y++)
{
for (x = 0; x < w; x++)
{
int a = sp[3];
int inva = a ? 256 * 255 / a : 0;
*b++ = (sp[0] * inva + 128)>>8;
*b++ = (sp[1] * inva + 128)>>8;
*b++ = (sp[2] * inva + 128)>>8;
*b++ = a;
sp += 4;
if (b == &buffer[sizeof(buffer)])
{
fz_write_data(ctx, out, buffer, sizeof(buffer));
b = buffer;
}
}
sp += stride;
}
if (b != buffer)
fz_write_data(ctx, out, buffer, b - buffer);
break;
case 5:
for (y = 0; y < end; y++)
{
for (x = 0; x < w; x++)
{
int a = sp[4];
int inva = a ? 256 * 255 / a : 0;
*b++ = (sp[0] * inva + 128)>>8;
*b++ = (sp[1] * inva + 128)>>8;
*b++ = (sp[2] * inva + 128)>>8;
*b++ = (sp[3] * inva + 128)>>8;
*b++ = a;
sp += 5;
if (b == &buffer[sizeof(buffer)])
{
fz_write_data(ctx, out, buffer, sizeof(buffer));
b = buffer;
}
}
sp += stride;
}
if (b != buffer)
fz_write_data(ctx, out, buffer, b - buffer);
break;
default:
for (y = 0; y < end; y++)
{
for (x = 0; x < w; x++)
{
int a = sp[n-1];
int inva = a ? 256 * 255 / a : 0;
int k;
for (k = 0; k < n-1; k++)
*b++ = (*sp++ * inva + 128)>>8;
*b++ = a;
sp++;
if (b >= &buffer[sizeof(buffer)] - n)
{
fz_write_data(ctx, out, buffer, b - buffer);
b = buffer;
}
}
sp += stride;
}
if (b != buffer)
fz_write_data(ctx, out, buffer, b - buffer);
break;
}
}
else
for (y = 0; y < end; y++)
{
fz_write_data(ctx, out, sp, w * n);
sp += stride;
}
}
fz_band_writer *fz_new_pam_band_writer(fz_context *ctx, fz_output *out)
{
fz_band_writer *writer = fz_new_band_writer(ctx, fz_band_writer, out);
writer->header = pam_write_header;
writer->band = pam_write_band;
return writer;
}
void
fz_write_pixmap_as_pam(fz_context *ctx, fz_output *out, fz_pixmap *pixmap)
{
fz_band_writer *writer = fz_new_pam_band_writer(ctx, out);
fz_try(ctx)
{
fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, 0, 0, 0, pixmap->colorspace, pixmap->seps);
fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);
}
fz_always(ctx)
fz_drop_band_writer(ctx, writer);
fz_catch(ctx)
fz_rethrow(ctx);
}
void
fz_save_pixmap_as_pam(fz_context *ctx, fz_pixmap *pixmap, const char *filename)
{
fz_band_writer *writer = NULL;
fz_output *out = fz_new_output_with_path(ctx, filename, 0);
fz_var(writer);
fz_try(ctx)
{
writer = fz_new_pam_band_writer(ctx, out);
fz_write_header(ctx, writer, pixmap->w, pixmap->h, pixmap->n, pixmap->alpha, 0, 0, 0, pixmap->colorspace, pixmap->seps);
fz_write_band(ctx, writer, pixmap->stride, pixmap->h, pixmap->samples);
fz_close_output(ctx, out);
}
fz_always(ctx)
{
fz_drop_band_writer(ctx, writer);
fz_drop_output(ctx, out);
}
fz_catch(ctx)
fz_rethrow(ctx);
}