Fix flipped subtitles with libass + avisynth

Originally committed to SVN as r5707.
This commit is contained in:
Thomas Goyne 2011-10-01 18:35:25 +00:00
parent 8624f923d9
commit a8caf35ebe

View file

@ -207,28 +207,36 @@ void LibassSubtitlesProvider::DrawSubtitles(AegiVideoFrame &frame,double time) {
// Prepare copy
int src_stride = img->stride;
int dst_stride = frame.pitch;
int dst_delta = dst_stride - img->w*4;
//int stride = std::min(src_stride,dst_stride);
const unsigned char *src = img->bitmap;
unsigned char *dst = frame.data + (img->dst_y * dst_stride + img->dst_x * 4);
unsigned int k,ck,t;
unsigned char *dst = frame.data;
if (frame.flipped) {
dst += dst_stride * (frame.h - 1);
dst_stride *= -1;
}
dst += (img->dst_y * dst_stride + img->dst_x * 4);
// Copy image to destination frame
for (int y = 0; y < img->h; y++) {
//memcpy(dst,src,stride);
unsigned char *dstp = dst;
for (int x = 0; x < img->w; ++x) {
k = ((unsigned)src[x]) * opacity / 255;
ck = 255 - k;
t = *dst;
*dst++ = (k*b + ck*t) / 255;
t = *dst;
*dst++ = (k*g + ck*t) / 255;
t = *dst;
*dst++ = (k*r + ck*t) / 255;
dst++;
unsigned int k = ((unsigned)src[x]) * opacity / 255;
unsigned int ck = 255 - k;
*dstp = (k * b + ck * *dstp) / 255;
++dstp;
*dstp = (k * g + ck * *dstp) / 255;
++dstp;
*dstp = (k * r + ck * *dstp) / 255;
++dstp;
++dstp;
}
dst += dst_delta;
dst += dst_stride;
src += src_stride;
}