mrmBot-Matrix/natives/watermark.cc
2023-03-15 10:09:09 -04:00

154 lines
5.2 KiB
C++

#include <map>
#include <vips/vips8>
#include "common.h"
using namespace std;
using namespace vips;
char *Watermark(string type, string *outType, char *BufferData,
size_t BufferLength, ArgumentMap Arguments, size_t *DataSize) {
string water = GetArgument<string>(Arguments, "water");
int gravity = GetArgument<int>(Arguments, "gravity");
bool resize = GetArgumentWithFallback<bool>(Arguments, "resize", false);
float yscale = GetArgumentWithFallback<float>(Arguments, "yscale", false);
bool append = GetArgumentWithFallback<bool>(Arguments, "append", false);
bool alpha = GetArgumentWithFallback<bool>(Arguments, "alpha", false);
bool flip = GetArgumentWithFallback<bool>(Arguments, "flip", false);
bool mc = MAP_HAS(Arguments, "mc");
string basePath = GetArgument<string>(Arguments, "basePath");
VOption *options = VImage::option()->set("access", "sequential");
VImage in =
VImage::new_from_buffer(BufferData, BufferLength, "",
type == "gif" ? options->set("n", -1) : options)
.colourspace(VIPS_INTERPRETATION_sRGB);
if (!in.has_alpha()) in = in.bandjoin(255);
string merged = basePath + water;
VImage watermark = VImage::new_from_file(merged.c_str());
int width = in.width();
int pageHeight = vips_image_get_page_height(in.get_image());
int nPages = vips_image_get_n_pages(in.get_image());
if (flip) {
watermark = watermark.flip(VIPS_DIRECTION_HORIZONTAL);
}
if (resize && append) {
watermark = watermark.resize((double)width / (double)watermark.width());
} else if (resize && yscale) {
watermark = watermark.resize(
(double)width / (double)watermark.width(),
VImage::option()->set("vscale", (double)(pageHeight * yscale) /
(double)watermark.height()));
} else if (resize) {
watermark =
watermark.resize((double)pageHeight / (double)watermark.height());
}
int x = 0, y = 0;
switch (gravity) {
case 1:
break;
case 2:
x = (width / 2) - (watermark.width() / 2);
break;
case 3:
x = width - watermark.width();
break;
case 5:
x = (width / 2) - (watermark.width() / 2);
y = (pageHeight / 2) - (watermark.height() / 2);
break;
case 6:
x = width - watermark.width();
y = (pageHeight / 2) - (watermark.height() / 2);
break;
case 8:
x = (width / 2) - (watermark.width() / 2);
y = pageHeight - watermark.height();
break;
case 9:
x = width - watermark.width();
y = pageHeight - watermark.height();
break;
}
vector<VImage> img;
int addedHeight = 0;
VImage contentAlpha;
VImage frameAlpha;
VImage bg;
VImage frame;
for (int i = 0; i < nPages; i++) {
VImage img_frame =
type == "gif" ? in.crop(0, i * pageHeight, width, pageHeight) : in;
if (append) {
VImage appended = img_frame.join(watermark, VIPS_DIRECTION_VERTICAL,
VImage::option()->set("expand", true));
addedHeight = watermark.height();
img.push_back(appended);
} else if (mc) {
VImage padded =
img_frame.embed(0, 0, width, pageHeight + 15,
VImage::option()->set("background", 0xffffff));
VImage composited =
padded.composite2(watermark, VIPS_BLEND_MODE_OVER,
VImage::option()
->set("x", width - 190)
->set("y", padded.height() - 22));
addedHeight = 15;
img.push_back(composited);
} else {
VImage composited;
if (alpha) {
if (i == 0) {
contentAlpha = watermark.extract_band(0).embed(
x, y, width, pageHeight,
VImage::option()->set("extend", "white"));
frameAlpha = watermark.extract_band(1).embed(
x, y, width, pageHeight,
VImage::option()->set("extend", "black"));
bg = frameAlpha.new_from_image({0, 0, 0}).copy(VImage::option()->set(
"interpretation", VIPS_INTERPRETATION_sRGB));
frame = bg.bandjoin(frameAlpha);
if (*outType == "jpg" || *outType == "jpeg") {
*outType = "png";
}
}
VImage content =
img_frame.extract_band(0, VImage::option()->set("n", 3))
.bandjoin(contentAlpha & img_frame.extract_band(3));
composited =
content.composite2(frame, VIPS_BLEND_MODE_OVER,
VImage::option()->set("x", x)->set("y", y));
} else {
composited =
img_frame.composite2(watermark, VIPS_BLEND_MODE_OVER,
VImage::option()->set("x", x)->set("y", y));
}
img.push_back(composited);
}
}
VImage final = VImage::arrayjoin(img, VImage::option()->set("across", 1));
final.set(VIPS_META_PAGE_HEIGHT, pageHeight + addedHeight);
void *buf;
final.write_to_buffer(
("." + *outType).c_str(), &buf, DataSize,
*outType == "gif"
? VImage::option()->set("dither", 0)->set("reoptimise", 1)
: 0);
return (char *)buf;
}