RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

pngdec: fix decoding of right column for 2/4bpp 

Fixes Ticket1146

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2013-01-03 23:40:22 +01:00
parent c5142a95a5
commit 9e36d9e4ed
1 changed files with 14 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

18
libavcodec/pngdec.c
View File

@ -784,15 +784,22 @@ static int decode_frame(AVCodecContext *avctx,
int i, j;
uint8_t *pd = s->current_picture->data[0];
for(j=0; j < s->height; j++) {
i = s->width/4;
if (s->color_type == PNG_COLOR_TYPE_PALETTE){
for(i=s->width/4-1; i>=0; i--) {
if ((s->width&3) >= 3) pd[4*i+2]= (pd[i]>>2)&3;
if ((s->width&3) >= 2) pd[4*i+1]= (pd[i]>>4)&3;
if ((s->width&3) >= 1) pd[4*i+0]= pd[i]>>6;
for(i--; i>=0; i--) {
pd[4*i+3]= pd[i] &3;
pd[4*i+2]= (pd[i]>>2)&3;
pd[4*i+1]= (pd[i]>>4)&3;
pd[4*i+0]= pd[i]>>6;
}
} else {
for(i=s->width/4-1; i>=0; i--) {
if ((s->width&3) >= 3) pd[4*i+2]= ((pd[i]>>2)&3)*0x55;
if ((s->width&3) >= 2) pd[4*i+1]= ((pd[i]>>4)&3)*0x55;
if ((s->width&3) >= 1) pd[4*i+0]= ( pd[i]>>6 )*0x55;
for(i--; i>=0; i--) {
pd[4*i+3]= ( pd[i] &3)*0x55;
pd[4*i+2]= ((pd[i]>>2)&3)*0x55;
pd[4*i+1]= ((pd[i]>>4)&3)*0x55;
@ -806,13 +813,16 @@ static int decode_frame(AVCodecContext *avctx,
int i, j;
uint8_t *pd = s->current_picture->data[0];
for(j=0; j < s->height; j++) {
i=s->width/2;
if (s->color_type == PNG_COLOR_TYPE_PALETTE){
for(i=s->width/2-1; i>=0; i--) {
if (s->width&1) pd[2*i+0]= pd[i]>>4;
for(i--; i>=0; i--) {
pd[2*i+1]= pd[i]&15;
pd[2*i+0]= pd[i]>>4;
}
} else {
for(i=s->width/2-1; i>=0; i--) {
if (s->width&1) pd[2*i+0]= (pd[i]>>4)*0x11;
for(i--; i>=0; i--) {
pd[2*i+1]= (pd[i]&15)*0x11;
pd[2*i+0]= (pd[i]>>4)*0x11;
}