/**
* Read a run length encoded SGI image.
* @param out_buf output buffer
* @param in_buf input buffer
* @param in_end end of input buffer
* @param s the current image state
* @return 0 if no error, else return error number.
*/
static int read_rle_sgi(unsigned char* out_buf, const uint8_t *in_buf,
const uint8_t *in_end, SgiState* s)
{
uint8_t *dest_row;
unsigned int len = s->height * s->depth * 4;
const uint8_t *start_table = in_buf;
unsigned int y, z;
unsigned int start_offset;
/* size of RLE offset and length tables */
if(len * 2 > in_end - in_buf) {
return AVERROR_INVALIDDATA;
}
in_buf -= SGI_HEADER_SIZE;
for (z = 0; z < s->depth; z++) {
dest_row = out_buf;
for (y = 0; y < s->height; y++) {
dest_row -= s->linesize;
start_offset = bytestream_get_be32(&start_table);
if(start_offset > in_end - in_buf) {
return AVERROR_INVALIDDATA;
}
if (expand_rle_row(in_buf + start_offset, in_end, dest_row + z,
dest_row + FFABS(s->linesize), s->depth) != s->width)
return AVERROR_INVALIDDATA;
}
}
return 0;
}
/**
* Read a run length encoded SGI image.
* @param out_buf output buffer
* @param s the current image state
* @return 0 if no error, else return error number.
*/
static int read_rle_sgi(uint8_t *out_buf, SgiState *s)
{
uint8_t *dest_row;
unsigned int len = s->height * s->depth * 4;
GetByteContext g_table = s->g;
unsigned int y, z;
unsigned int start_offset;
/* size of RLE offset and length tables */
if (len * 2 > bytestream2_get_bytes_left(&s->g)) {
return AVERROR_INVALIDDATA;
}
for (z = 0; z < s->depth; z++) {
dest_row = out_buf;
for (y = 0; y < s->height; y++) {
dest_row -= s->linesize;
start_offset = bytestream2_get_be32(&g_table);
bytestream2_seek(&s->g, start_offset, SEEK_SET);
if (expand_rle_row(s, dest_row + z, dest_row + FFABS(s->linesize),
s->depth) != s->width) {
return AVERROR_INVALIDDATA;
}
}
}
return 0;
}
/* read a run length encoded sgi image */
static int read_rle_sgi(const SGIInfo *sgi_info,
AVPicture *pict, ByteIOContext *f)
{
uint8_t *dest_row;
unsigned long *start_table;
int y, z, xsize, ysize, zsize, tablen;
long start_offset;
int ret = 0;
xsize = sgi_info->xsize;
ysize = sgi_info->ysize;
zsize = sgi_info->zsize;
/* skip header */
url_fseek(f, SGI_HEADER_SIZE, SEEK_SET);
/* size of rle offset and length tables */
tablen = ysize * zsize * sizeof(long);
start_table = (unsigned long *)av_malloc(tablen);
if (!get_buffer(f, (uint8_t *)start_table, tablen)) {
ret = AVERROR_IO;
goto fail;
}
/* skip run length table */
url_fseek(f, tablen, SEEK_CUR);
for (z = 0; z < zsize; z++) {
for (y = 0; y < ysize; y++) {
dest_row = pict->data[0] + (ysize - 1 - y) * (xsize * zsize);
start_offset = BE_32(&start_table[y + z * ysize]);
/* don't seek if already at the next rle start offset */
if (url_ftell(f) != start_offset) {
url_fseek(f, start_offset, SEEK_SET);
}
if (expand_rle_row(f, dest_row, z, zsize) != xsize) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
}
}
fail:
av_free(start_table);
return ret;
}
