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ffmpeg.wasm-core
Commit b2e95e01 authored by Michael Niedermayer's avatar Michael Niedermayer
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avcodec/faxcompr: Factor decode_uncompressed() out 

Signed-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parent fedc4226
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Showing with 85 additions and 127 deletions
libavcodec/faxcompr.c
View file @ b2e95e01
......@@ -122,6 +122,77 @@ av_cold void ff_ccitt_unpack_init(void)
initialized = 1;
}
static int decode_uncompressed(AVCodecContext *avctx, GetBitContext *gb,
unsigned int *pix_left, int **runs,
const int *runend, int *mode)
{
int eob = 0;
int newmode;
int saved_run = 0;
do {
int cwi, k;
int cw = 0;
int codes[2];
do {
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;
}
if (*pix_left <= saved_run) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n");
return AVERROR_INVALIDDATA;
}
*pix_left -= saved_run;
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;
}
if (*pix_left <= saved_run) {
if (*pix_left == saved_run)
return 1;
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of boundsE\n");
return AVERROR_INVALIDDATA;
}
*pix_left -= saved_run;
saved_run = 0;
*mode = !*mode;
if (newmode != *mode) { //FIXME CHECK
*(*runs)++ = 0;
*mode = newmode;
}
return 0;
}
static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb,
unsigned int pix_left, int *runs,
......@@ -150,72 +221,13 @@ static int decode_group3_1d_line(AVCodecContext *avctx, GetBitContext *gb,
mode = !mode;
} else if ((int)t == -1) {
if (show_bits(gb, 12) == 15) {
int eob = 0;
int newmode;
int saved_run = 0;
int ret;
skip_bits(gb, 12);
do {
int cwi, k;
int cw = 0;
int codes[2];
do {
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;
}
if (pix_left <= saved_run) {
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of bounds\n");
return AVERROR_INVALIDDATA;
}
pix_left -= saved_run;
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;
}
if (pix_left <= saved_run) {
if (pix_left == saved_run)
break;
av_log(avctx, AV_LOG_ERROR, "uncompressed run went out of boundsE\n");
return AVERROR_INVALIDDATA;
}
pix_left -= saved_run;
saved_run = 0;
mode = !mode;
if (newmode != mode) { //FIXME CHECK
*runs++ = 0;
mode = newmode;
}
ret = decode_uncompressed(avctx, gb, &pix_left, &runs, runend, &mode);
if (ret < 0) {
return ret;
} else if (ret)
break;
} else {
av_log(avctx, AV_LOG_ERROR, "Incorrect code\n");
return AVERROR_INVALIDDATA;
......@@ -282,73 +294,19 @@ static int decode_group3_2d_line(AVCodecContext *avctx, GetBitContext *gb,
} else if (cmode == 9 || cmode == 10) {
int xxx = get_bits(gb, 3);
if (cmode == 9 && xxx == 7) {
int eob = 0;
int newmode;
int ret;
int pix_left = width - offs;
if (saved_run) {
av_log(avctx, AV_LOG_ERROR, "saved run %d on entering uncompressed mode\n", saved_run);
return AVERROR_INVALIDDATA;
}
do {
int cwi, k;
int cw = 0;
int codes[2];
do {
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;
}
ret = decode_uncompressed(avctx, gb, &pix_left, &runs, runend, &mode);
offs = width - pix_left;
if (ret < 0) {
return ret;
} else if (ret)
break;
} else {
avpriv_report_missing_feature(avctx, "Special mode %d xxx=%d support", cmode, xxx);
return AVERROR_PATCHWELCOME;
......
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