Changed the rle encoder a little and made it more universal.

Not only the repeated byte is calculated as (count ^ xor) + add
but also the raw encoding lenth byte is calculated as that too
patch by Xiaohui Sun sunxiaohui  dsp ac cn

Originally committed as revision 8602 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Xiaohui Sun 2007-04-03 06:40:21 +00:00 committed by Michael Niedermayer
parent 65df54496e
commit b25514a43f
3 changed files with 9 additions and 6 deletions

View File

@ -55,7 +55,8 @@ static int count_pixels(const uint8_t *start, int len, int bpp, int same)
return count;
}
int ff_rle_encode(uint8_t *outbuf, int out_size, const uint8_t *ptr , int bpp, int w, int8_t add, uint8_t xor)
int ff_rle_encode(uint8_t *outbuf, int out_size, const uint8_t *ptr , int bpp, int w,
int8_t add_rep, uint8_t xor_rep,int8_t add_raw,uint8_t xor_raw)
{
int count, x;
uint8_t *out = outbuf;
@ -64,13 +65,13 @@ int ff_rle_encode(uint8_t *outbuf, int out_size, const uint8_t *ptr , int bpp, i
/* see if we can encode the next set of pixels with RLE */
if((count = count_pixels(ptr, w-x, bpp, 1)) > 1) {
if(out + bpp + 1 > outbuf + out_size) return -1;
*out++ = (count ^ xor) + add;
*out++ = (count ^ xor_rep) + add_rep;
memcpy(out, ptr, bpp);
out += bpp;
} else {
/* fall back on uncompressed */
count = count_pixels(ptr, w-x, bpp, 0);
*out++ = count - 1;
*out++ = (count ^ xor_raw) + add_raw;
if(out + bpp*count > outbuf + out_size) return -1;
memcpy(out, ptr, bpp * count);

View File

@ -23,7 +23,8 @@
#define RLE_H
/**
* RLE compress the row, with maximum size of out_size. Value before repeated bytes is (count ^ xor) + add.
* RLE compress the row, with maximum size of out_size. Value before repeated bytes is (count ^ xor_rep) + add_rep.
* Value before raw bytes is (count ^ xor_raw) + add_raw.
* @param outbuf Output buffer
* @param out_size Maximum output size
* @param ptr Input buffer
@ -31,6 +32,7 @@
* @param w Image width
* @return Size of output in bytes, or -1 if larger than out_size
*/
int ff_rle_encode(uint8_t *outbuf, int out_size, const uint8_t *inbuf, int bpp, int w, int8_t add, uint8_t xor);
int ff_rle_encode(uint8_t *outbuf, int out_size, const uint8_t *inbuf, int bpp, int w,
int8_t add_rep, uint8_t xor_rep, int8_t add_raw, uint8_t xor_raw);
#endif /* RLE_H */

View File

@ -41,7 +41,7 @@ static int targa_encode_rle(uint8_t *outbuf, int out_size, AVFrame *pic,
out = outbuf;
for(y = 0; y < h; y ++) {
ret = ff_rle_encode(out, out_size, pic->data[0] + pic->linesize[0] * y, bpp, w, 0x7f, 0);
ret = ff_rle_encode(out, out_size, pic->data[0] + pic->linesize[0] * y, bpp, w, 0x7f, 0, -1, 0);
if(ret == -1){
return -1;
}