Skip to content

F
ffmpeg.wasm-core
Commit b2e95e01 authored by Michael Niedermayer's avatar Michael Niedermayer
Browse files
Options

avcodec/faxcompr: Factor decode_uncompressed() out 

Signed-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parent fedc4226
Show whitespace changes
Inline Side-by-side
Showing with 85 additions and 127 deletions
libavcodec/faxcompr.c
View file @ b2e95e01
...@@ -122,38 +122,13 @@ av_cold void ff_ccitt_unpack_init(void) ...@@ -122,38 +122,13 @@ av_cold void ff_ccitt_unpack_init(void)
initialized = 1; initialized = 1;
} }
static int decode_uncompressed(AVCodecContext *avctx, GetBitContext *gb,
static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb, unsigned int *pix_left, int **runs,
unsigned int pix_left, int *runs, const int *runend, int *mode)
const int *runend)
{ {
int mode = 0;
unsigned int run = 0;
unsigned int t;
for (;;) {
t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2);
run += t;
if (t < 64) {
*runs++ = run;
if (runs >= runend) {
av_log(avctx, AV_LOG_ERROR, "Run overrun\n");
return AVERROR_INVALIDDATA;
}
if (pix_left <= run) {
if (pix_left == run)
break;
av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n");
return AVERROR_INVALIDDATA;
}
pix_left -= run;
run = 0;
mode = !mode;
} else if ((int)t == -1) {
if (show_bits(gb, 12) == 15) {
int eob = 0; int eob = 0;
int newmode; int newmode;
int saved_run = 0; int saved_run = 0;
skip_bits(gb, 12);
do { do {
int cwi, k; int cwi, k;
...@@ -180,42 +155,79 @@ static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb, ...@@ -180,42 +155,79 @@ static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb,
for (k = 0; k < 2; k++) { for (k = 0; k < 2; k++) {
if (codes[k]) { if (codes[k]) {
if (mode == k) { if (*mode == k) {
*runs++ = saved_run; *(*runs)++ = saved_run;
if (runs >= runend) { if (*runs >= runend) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n"); av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n");
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
} }
if (pix_left <= saved_run) { if (*pix_left <= saved_run) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n"); av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n");
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
} }
pix_left -= saved_run; *pix_left -= saved_run;
saved_run = 0; saved_run = 0;
mode = !mode; *mode = !*mode;
} }
saved_run += codes[k]; saved_run += codes[k];
} }
} }
} while (!eob); } while (!eob);
*runs++ = saved_run; *(*runs)++ = saved_run;
if (runs >= runend) { if (*runs >= runend) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n"); av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n");
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
} }
if (pix_left <= saved_run) { if (*pix_left <= saved_run) {
if (pix_left == saved_run) if (*pix_left == saved_run)
break; return 1;
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of boundsE\n"); av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of boundsE\n");
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
} }
pix_left -= saved_run; *pix_left -= saved_run;
saved_run = 0; saved_run = 0;
mode = !mode; *mode = !*mode;
if (newmode != mode) { //FIXME CHECK if (newmode != *mode) { //FIXME CHECK
*runs++ = 0; *(*runs)++ = 0;
mode = newmode; *mode = newmode;
} }
return 0;
}
static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb,
unsigned int pix_left, int *runs,
const int *runend)
{
int mode = 0;
unsigned int run = 0;
unsigned int t;
for (;;) {
t = get_vlc2(gb, ccitt_vlc[mode].table, 9, 2);
run += t;
if (t < 64) {
*runs++ = run;
if (runs >= runend) {
av_log(avctx, AV_LOG_ERROR, "Run overrun\n");
return AVERROR_INVALIDDATA;
}
if (pix_left <= run) {
if (pix_left == run)
break;
av_log(avctx, AV_LOG_ERROR, "Run went out of bounds\n");
return AVERROR_INVALIDDATA;
}
pix_left -= run;
run = 0;
mode = !mode;
} else if ((int)t == -1) {
if (show_bits(gb, 12) == 15) {
int ret;
skip_bits(gb, 12);
ret = decode_uncompressed(avctx, gb, &pix_left, &runs, runend, &mode);
if (ret < 0) {
return ret;
} else if (ret)
break;
} else { } else {
av_log(avctx, AV_LOG_ERROR, "Incorrect code\n"); av_log(avctx, AV_LOG_ERROR, "Incorrect code\n");
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
...@@ -282,73 +294,19 @@ static int decode_group3_2d_line(AVCodecContext *avctx, GetBitContext *gb, ...@@ -282,73 +294,19 @@ static int decode_group3_2d_line(AVCodecContext *avctx, GetBitContext *gb,
} else if (cmode == 9 || cmode == 10) { } else if (cmode == 9 || cmode == 10) {
int xxx = get_bits(gb, 3); int xxx = get_bits(gb, 3);
if (cmode == 9 && xxx == 7) { if (cmode == 9 && xxx == 7) {
int eob = 0; int ret;
int newmode; int pix_left = width - offs;
if (saved_run) { if (saved_run) {
av_log(avctx, AV_LOG_ERROR, "saved run %d on entering uncompressed mode\n", saved_run); av_log(avctx, AV_LOG_ERROR, "saved run %d on entering uncompressed mode\n", saved_run);
return AVERROR_INVALIDDATA; return AVERROR_INVALIDDATA;
} }
ret = decode_uncompressed(avctx, gb, &pix_left, &runs, runend, &mode);
do { offs = width - pix_left;
int cwi, k; if (ret < 0) {
int cw = 0; return ret;
int codes[2]; } else if (ret)
do { break;
cwi = show_bits(gb, 11);
if (!cwi) {
av_log(avctx, AV_LOG_ERROR, "Invalid uncompressed codeword\n");
return AVERROR_INVALIDDATA;
}
cwi = 10 - av_log2(cwi);
skip_bits(gb, cwi + 1);
if (cwi > 5) {
newmode = get_bits1(gb);
eob = 1;
cwi -= 6;
}
cw += cwi;
} while(cwi == 5);
codes[0] = cw;
codes[1] = !eob;
for (k = 0; k < 2; k++) {
if (codes[k]) {
if (mode == k) {
*runs++ = saved_run;
if (runs >= runend) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n");
return AVERROR_INVALIDDATA;
}
offs += saved_run;
if (offs > width || run > width) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n");
return AVERROR_INVALIDDATA;
}
saved_run = 0;
mode = !mode;
}
saved_run += codes[k];
}
}
} while (!eob);
*runs++ = saved_run;
if (runs >= runend) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run overrun\n");
return AVERROR_INVALIDDATA;
}
offs += saved_run;
if (offs > width || run > width) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n");
return AVERROR_INVALIDDATA;
}
saved_run = 0;
mode = !mode;
if (newmode != mode) { //FIXME CHECK
*runs++ = 0;
mode = newmode;
}
} else { } else {
avpriv_report_missing_feature(avctx, "Special mode %d xxx=%d support", cmode, xxx); avpriv_report_missing_feature(avctx, "Special mode %d xxx=%d support", cmode, xxx);
return AVERROR_PATCHWELCOME; return AVERROR_PATCHWELCOME;
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment