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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-23 12:43:46 +02:00
FFmpeg/libavcodec/scpr3.c
Michael Niedermayer cc7e984a05
avcodec/scpr3: Check bx
Fixes: Out of array access
Fixes: 55102/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SCPR_fuzzer-4877396618903552

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2023-01-17 12:54:54 +01:00

1212 lines
32 KiB
C

/*
* ScreenPressor version 3 decoder
*
* Copyright (c) 2017 Paul B Mahol
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavutil/qsort.h"
#include "avcodec.h"
#include "bytestream.h"
#include "scpr.h"
static void renew_table3(uint32_t nsym, uint32_t *cntsum,
uint16_t *freqs, uint16_t *freqs1,
uint16_t *cnts, uint8_t *dectab)
{
uint32_t a = 0, b = 4096 / nsym, c = b - (b >> 1);
*cntsum = c * nsym;
for (int d = 0; d < nsym; d++) {
freqs[d] = b;
freqs1[d] = a;
cnts[d] = c;
for (int q = a + 128 - 1 >> 7, f = (a + b - 1 >> 7) + 1; q < f; q++)
dectab[q] = d;
a += b;
}
}
static void reinit_tables3(SCPRContext * s)
{
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 4096; j++) {
PixelModel3 *m = &s->pixel_model3[i][j];
m->type = 0;
}
}
for (int i = 0; i < 6; i++) {
renew_table3(256, &s->run_model3[i].cntsum,
s->run_model3[i].freqs[0], s->run_model3[i].freqs[1],
s->run_model3[i].cnts, s->run_model3[i].dectab);
}
renew_table3(256, &s->range_model3.cntsum,
s->range_model3.freqs[0], s->range_model3.freqs[1],
s->range_model3.cnts, s->range_model3.dectab);
renew_table3(5, &s->fill_model3.cntsum,
s->fill_model3.freqs[0], s->fill_model3.freqs[1],
s->fill_model3.cnts, s->fill_model3.dectab);
renew_table3(256, &s->count_model3.cntsum,
s->count_model3.freqs[0], s->count_model3.freqs[1],
s->count_model3.cnts, s->count_model3.dectab);
for (int i = 0; i < 4; i++) {
renew_table3(16, &s->sxy_model3[i].cntsum,
s->sxy_model3[i].freqs[0], s->sxy_model3[i].freqs[1],
s->sxy_model3[i].cnts, s->sxy_model3[i].dectab);
}
for (int i = 0; i < 2; i++) {
renew_table3(512, &s->mv_model3[i].cntsum,
s->mv_model3[i].freqs[0], s->mv_model3[i].freqs[1],
s->mv_model3[i].cnts, s->mv_model3[i].dectab);
}
for (int i = 0; i < 6; i++) {
renew_table3(6, &s->op_model3[i].cntsum,
s->op_model3[i].freqs[0], s->op_model3[i].freqs[1],
s->op_model3[i].cnts, s->op_model3[i].dectab);
}
}
static int decode3(GetByteContext *gb, RangeCoder *rc, uint32_t a, uint32_t b)
{
uint32_t code = a * (rc->code >> 12) + (rc->code & 0xFFF) - b;
while (code < 0x800000 && bytestream2_get_bytes_left(gb) > 0)
code = bytestream2_get_byteu(gb) | (code << 8);
rc->code = code;
return 0;
}
static void rescale(PixelModel3 *m, int *totfr)
{
uint32_t a;
a = 256 - m->size;
for (int b = 0; b < m->size; b++) {
m->freqs[b] -= m->freqs[b] >> 1;
a += m->freqs[b];
}
*totfr = a;
}
static int add_symbol(PixelModel3 *m, int index, uint32_t symbol, int *totfr, int max)
{
if (m->size == max)
return 0;
for (int c = m->size - 1; c >= index; c--) {
m->symbols[c + 1] = m->symbols[c];
m->freqs[c + 1] = m->freqs[c];
}
m->symbols[index] = symbol;
m->freqs[index] = 50;
m->size++;
if (m->maxpos >= index)
m->maxpos++;
*totfr += 50;
if (*totfr + 50 > 4096)
rescale(m, totfr);
return 1;
}
static int decode_adaptive45(PixelModel3 *m, int rccode, uint32_t *value,
uint16_t *a, uint16_t *b, uint32_t *c, int max)
{
uint32_t q, g, maxpos, d, e = *c, totfr = *c;
int ret;
for (d = 0; e <= 2048; d++)
e <<= 1;
maxpos = m->maxpos;
rccode >>= d;
*c = m->freqs[maxpos];
m->freqs[maxpos] += 4096 - e >> d;
for (q = 0, g = 0, e = 0; q < m->size; q++) {
uint32_t f = m->symbols[q];
uint32_t p = e + f - g;
uint32_t k = m->freqs[q];
if (rccode < p) {
*value = rccode - e + g;
*b = rccode << d;
*a = 1 << d;
m->freqs[maxpos] = *c;
ret = add_symbol(m, q, *value, &totfr, max);
*c = totfr;
return ret;
}
if (p + k > rccode) {
*value = f;
e += *value - g;
*b = e << d;
*a = k << d;
m->freqs[maxpos] = *c;
m->freqs[q] += 50;
totfr += 50;
if ((q != maxpos) && (m->freqs[q] > m->freqs[maxpos]))
m->maxpos = q;
if (totfr + 50 > 4096)
rescale(m, &totfr);
*c = totfr;
return 1;
}
e += f - g + k;
g = f + 1;
}
m->freqs[maxpos] = *c;
*value = g + rccode - e;
*b = rccode << d;
*a = 1 << d;
ret = add_symbol(m, q, *value, &totfr, max);
*c = totfr;
return ret;
}
static int update_model6_to_7(PixelModel3 *m)
{
PixelModel3 n = {0};
int c, d, e, f, k, p, length, i, j, index;
uint16_t *freqs, *freqs1, *cnts;
n.type = 7;
length = m->length;
freqs = n.freqs;
freqs1 = n.freqs1;
cnts = n.cnts;
n.cntsum = m->cnts[length];
for (i = 0; i < length; i++) {
if (!m->cnts[i])
continue;
index = m->symbols[i];
freqs[index] = m->freqs[2 * i];
freqs1[index] = m->freqs[2 * i + 1];
cnts[index] = m->cnts[i];
}
c = 1 << m->fshift;
d = c - (c >> 1);
for (j = 0, e = 0; j < 256; j++) {
f = freqs[j];
if (!f) {
f = c;
freqs[j] = c;
freqs1[j] = e;
cnts[j] = d;
}
p = (e + 127) >> 7;
k = ((f + e - 1) >> 7) + 1;
if (k > FF_ARRAY_ELEMS(n.dectab))
return AVERROR_INVALIDDATA;
for (i = 0; i < k - p; i++)
n.dectab[p + i] = j;
e += f;
}
memcpy(m, &n, sizeof(n));
return 0;
}
static void calc_sum(PixelModel3 *m)
{
uint32_t a;
int len;
len = m->length;
a = 256 - m->size << (m->fshift > 0 ? m->fshift - 1 : 0);
for (int c = 0; c < len; c++)
a += m->cnts[c];
m->cnts[len] = a;
}
static void rescale_dec(PixelModel3 *m)
{
uint16_t cnts[256] = {0};
uint16_t freqs[512] = {0};
int b, c, e, g;
uint32_t a;
for (a = 1 << (0 < m->fshift ? m->fshift - 1 : 0), b = 0; b < 256; b++)
cnts[b] = a;
for (a = 0, b = m->size; a < b; a++)
cnts[m->symbols[a]] = m->cnts[a];
for (b = a = 0; b < 256; b++) {
freqs[2 * b] = cnts[b];
freqs[2 * b + 1] = a;
a += cnts[b];
}
if (m->fshift > 0)
m->fshift--;
a = 256 - m->size << (0 < m->fshift ? m->fshift - 1 : 0);
for (b = 0, c = m->size; b < c; b++) {
m->cnts[b] -= m->cnts[b] >> 1;
a = a + m->cnts[b];
e = m->symbols[b];
g = freqs[2 * e + 1];
m->freqs[2 * b] = freqs[2 * e];
m->freqs[2 * b + 1] = g;
}
m->cnts[m->length] = a;
}
static int update_model5_to_6(PixelModel3 *m, uint8_t value)
{
PixelModel3 n = {0};
int c, d, e, f, g, k, q, p;
n.type = 6;
n.length = 32;
for (c = m->size, d = 256 - c, e = 0; e < c; e++)
d = d + m->freqs[e];
for (e = 0; d <= 2048; e++)
d <<= 1;
for (q = d = 0, g = q = 0; g < c; g++) {
p = m->symbols[g];
d = d + (p - q);
q = m->freqs[g];
k = q << e;
n.freqs[2 * g] = k;
n.freqs[2 * g + 1] = d << e;
n.cnts[g] = k - (k >> 1);
n.symbols[g] = p;
d += q;
q = p + 1;
}
n.fshift = e;
e = 1 << n.fshift;
d = 0;
if (value > 0) {
d = -1;
for (p = f = g = 0; p < c; p++) {
k = n.symbols[p];
if (k > d && k < value) {
d = k;
g = n.freqs[2 * p];
f = n.freqs[2 * p + 1];
}
}
d = 0 < g ? f + g + (value - d - 1 << n.fshift) : value << n.fshift;
}
n.freqs[2 * c] = e;
n.freqs[2 * c + 1] = d;
n.cnts[c] = e - (e >> 1);
n.symbols[c] = value;
n.size = c + 1;
e = 25 << n.fshift;
n.cnts[c] += e;
n.cnts[32] += e;
if (n.cnts[32] + e > 4096)
rescale_dec(&n);
calc_sum(&n);
for (c = 0, e = n.size - 1; c < e; c++) {
for (g = c + 1, f = n.size; g < f; g++) {
if (q = n.freqs[2 * g], k = n.freqs[2 * c], q > k) {
int l = n.freqs[2 * c + 1];
int h = n.freqs[2 * g + 1];
n.freqs[2 * c] = q;
n.freqs[2 * c + 1] = h;
n.freqs[2 * g] = k;
n.freqs[2 * g + 1] = l;
FFSWAP(uint16_t, n.cnts[c], n.cnts[g]);
FFSWAP(uint8_t, n.symbols[c], n.symbols[g]);
}
}
}
memcpy(m, &n, sizeof(n));
return 0;
}
static void grow_dec(PixelModel3 *m)
{
int a;
a = 2 * m->length;
m->cnts[2 * m->length] = m->cnts[m->length];
m->length = a;
}
static int add_dec(PixelModel3 *m, int sym, int f1, int f2)
{
int size;
if (m->size >= 40 || m->size >= m->length)
return -1;
size = m->size;
m->symbols[size] = sym;
m->freqs[2 * size] = f1;
m->freqs[2 * size + 1] = f2;
m->cnts[size] = f1 - (f1 >> 1);
m->size++;
return size;
}
static void incr_cntdec(PixelModel3 *m, int a)
{
int b, len, d, e, g;
b = 25 << m->fshift;
len = m->length;
m->cnts[a] += b;
m->cnts[len] += b;
if (a > 0 && m->cnts[a] > m->cnts[a - 1]) {
FFSWAP(uint16_t, m->cnts[a], m->cnts[a - 1]);
d = m->freqs[2 * a];
e = m->freqs[2 * a + 1];
g = m->freqs[2 * (a - 1) + 1];
m->freqs[2 * a] = m->freqs[2 * (a - 1)];
m->freqs[2 * a + 1] = g;
g = a - 1;
m->freqs[2 * g] = d;
m->freqs[2 * g + 1] = e;
FFSWAP(uint8_t, m->symbols[a], m->symbols[a - 1]);
}
if (m->cnts[len] + b > 4096)
rescale_dec(m);
}
static int decode_adaptive6(PixelModel3 *m, uint32_t code, uint32_t *value,
uint16_t *a, uint16_t *b)
{
int c, d, e, f, g, q;
for (c = 0, d = 0, e = 0, f = 0, g = 0, q = m->size; g < q; g++) {
uint32_t p = m->freqs[2 * g + 1];
if (p <= code) {
uint32_t k = m->freqs[2 * g];
if (p + k > code) {
*value = m->symbols[g];
*a = k;
*b = p;
incr_cntdec(m, g);
return 1;
}
if (p >= d) {
c = k;
d = p;
e = m->symbols[g];
}
}
}
g = 1 << m->fshift;
q = f = 0;
if (c > 0) {
f = code - (d + c) >> m->fshift;
q = f + e + 1;
f = d + c + (f << m->fshift);
} else {
q = code >> m->fshift;
f = q << m->fshift;
}
*a = g;
*b = f;
*value = q;
c = add_dec(m, q, g, f);
if (c < 0) {
if (m->length == 64)
return 0;
grow_dec(m);
c = add_dec(m, q, g, f);
}
incr_cntdec(m, c);
return 1;
}
static int cmpbytes(const void *p1, const void *p2)
{
int left = *(const uint8_t *)p1;
int right = *(const uint8_t *)p2;
return FFDIFFSIGN(left, right);
}
static int update_model1_to_2(PixelModel3 *m, uint32_t val)
{
PixelModel3 n = {0};
int i, b;
n.type = 2;
n.size = m->size + 1;
b = m->size;
for (i = 0; i < b; i++)
n.symbols[i] = m->symbols[i];
n.symbols[b] = val;
memcpy(m, &n, sizeof(n));
return 0;
}
static int update_model1_to_4(PixelModel3 *m, uint32_t val)
{
PixelModel3 n = {0};
int size, i;
size = m->size;
n.type = 4;
n.size = size;
for (i = 0; i < n.size; i++) {
n.symbols[i] = m->symbols[i];
}
AV_QSORT(n.symbols, size, uint8_t, cmpbytes);
for (i = 0; i < n.size; i++) {
if (val == n.symbols[i]) {
n.freqs[i] = 100;
n.maxpos = i;
} else {
n.freqs[i] = 50;
}
}
memcpy(m, &n, sizeof(n));
return 0;
}
static int update_model1_to_5(PixelModel3 *m, uint32_t val)
{
int i, size, freqs;
uint32_t a;
update_model1_to_4(m, val);
size = m->size;
a = 256 - size;
for (i = 0; i < size; i++, a += freqs)
freqs = m->freqs[i];
m->type = 5;
m->cntsum = a;
return 0;
}
static int decode_static1(PixelModel3 *m, uint32_t val)
{
uint32_t size;
size = m->size;
for (int i = 0; i < size; i++) {
if (val == m->symbols[i]) {
if (size <= 4)
return update_model1_to_4(m, val);
else
return update_model1_to_5(m, val);
}
}
if (size >= 14)
return update_model1_to_2(m, val);
m->symbols[size] = val;
m->size++;
return 0;
}
static int update_model2_to_6(PixelModel3 *m, uint8_t value, int a4)
{
PixelModel3 n = {0};
int c, d, e, f, g, q;
n.type = 6;
n.length = a4;
memset(n.symbols, 1u, a4);
c = m->size;
d = 256 - c + (64 * c + 64);
for (e = 0; d <= 2048; e++) {
d <<= 1;
}
g = q = 0;
AV_QSORT(m->symbols, c, uint8_t, cmpbytes);
for (f = d = 0; f < c; f++) {
int p = f;
int k = m->symbols[p];
int l;
g = g + (k - q);
if (k == value) {
d = p;
q = 128;
} else {
q = 64;
}
l = q << e;
n.freqs[2 * p] = l;
n.freqs[2 * p + 1] = g << e;
n.symbols[p] = k;
n.cnts[p] = l - (l >> 1);
g += q;
q = k + 1;
}
n.size = c;
n.fshift = e;
calc_sum(&n);
if (d > 0) {
c = n.freqs[0];
e = n.freqs[1];
g = n.freqs[2 * d + 1];
n.freqs[0] = n.freqs[2 * d];
n.freqs[1] = g;
n.freqs[2 * d] = c;
n.freqs[2 * d + 1] = e;
FFSWAP(uint16_t, n.cnts[0], n.cnts[d]);
FFSWAP(uint8_t, n.symbols[0], n.symbols[d]);
}
memcpy(m, &n, sizeof(n));
return 0;
}
static int update_model2_to_3(PixelModel3 *m, uint32_t val)
{
PixelModel3 n = {0};
uint32_t size;
n.type = 3;
n.size = m->size + 1;
size = m->size;
for (int i = 0; i < size; i++)
n.symbols[i] = m->symbols[i];
n.symbols[size] = val;
memcpy(m, &n, sizeof(n));
return 0;
}
static int decode_static2(PixelModel3 *m, uint32_t val)
{
uint32_t size;
size = m->size;
for (int i = 0; i < size; i++) {
if (val == m->symbols[i]) {
int a;
if (m->size <= 32)
a = 32;
else
a = 64;
return update_model2_to_6(m, val, a);
}
}
if (size >= 64)
return update_model2_to_3(m, val);
m->symbols[size] = val;
m->size++;
return 0;
}
static int update_model3_to_7(PixelModel3 *m, uint8_t value)
{
PixelModel3 n = {0};
int c, d, e, f, g, q;
n.type = 7;
for (c = 0; c < 256; c++) {
d = c;
n.freqs[d] = 1;
n.cnts[d] = 1;
}
for (c = m->size, d = (4096 - (256 - c)) / (c + 1) | 0, e = d - (d >> 1), g = 0; g < c;) {
q = g++;
q = m->symbols[q];
n.freqs[q] = d;
n.cnts[q] = e;
}
n.freqs[value] += d;
n.cnts[value] += 16;
for (d = c = n.cntsum = 0; 256 > d; d++) {
e = d;
n.cntsum += n.cnts[e];
n.freqs1[e] = c;
g = n.freqs[e];
f = (c + g - 1 >> 7) + 1;
if (f > FF_ARRAY_ELEMS(n.dectab))
return AVERROR_INVALIDDATA;
for (q = c + 128 - 1 >> 7; q < f; q++) {
n.dectab[q] = e;
}
c += g;
}
memcpy(m, &n, sizeof(n));
return 0;
}
static int decode_static3(PixelModel3 *m, uint32_t val)
{
uint32_t size = m->size;
for (int i = 0; i < size; i++) {
if (val == m->symbols[i])
return update_model3_to_7(m, val);
}
if (size >= 256)
return 0;
m->symbols[size] = val;
m->size++;
return 0;
}
static void sync_code3(GetByteContext *gb, RangeCoder *rc)
{
rc->code1++;
if (rc->code1 == 0x20000) {
rc->code = bytestream2_get_le32(gb);
rc->code1 = 0;
}
}
static int decode_value3(SCPRContext *s, uint32_t max, uint32_t *cntsum,
uint16_t *freqs1, uint16_t *freqs2,
uint16_t *cnts, uint8_t *dectable,
uint32_t *value)
{
GetByteContext *gb = &s->gb;
RangeCoder *rc = &s->rc;
uint32_t r, y, a, b, e, g, q;
r = dectable[(rc->code & 0xFFFu) >> 7];
if (r < max) {
while (freqs2[r + 1] <= (rc->code & 0xFFF)) {
if (++r >= max)
break;
}
}
if (r > max)
return AVERROR_INVALIDDATA;
cnts[r] += 16;
a = freqs1[r];
b = freqs2[r];
*cntsum += 16;
if (*cntsum + 16 > 4096) {
*cntsum = 0;
for (int c = 0, i = 0; i < max + 1; i++) {
e = cnts[i];
freqs2[i] = c;
freqs1[i] = e;
g = (c + 127) >> 7;
c += e;
q = ((c - 1) >> 7) + 1;
if (q > g) {
for (int j = 0; j < q - g; j++)
dectable[j + g] = i;
}
y = e - (e >> 1);
cnts[i] = y;
*cntsum += y;
}
}
decode3(gb, rc, a, b);
sync_code3(gb, rc);
*value = r;
return 0;
}
static void calc_sum5(PixelModel3 *m)
{
uint32_t a;
a = 256 - m->size;
for (int b = 0; b < m->size; b++)
a += m->freqs[b];
m->cntsum = a;
}
static int update_model4_to_5(PixelModel3 *m, uint32_t value)
{
PixelModel3 n = {0};
int c, e, g, totfr;
n.type = 5;
for (c = 0, e = 0; c < m->size && m->symbols[c] < value; c++) {
n.symbols[c] = m->symbols[c];
e += n.freqs[c] = m->freqs[c];
}
g = c;
n.symbols[g] = value;
e += n.freqs[g++] = 50;
for (; c < m->size; g++, c++) {
n.symbols[g] = m->symbols[c];
e += n.freqs[g] = m->freqs[c];
}
n.size = m->size + 1;
if (e > 4096)
rescale(&n, &totfr);
calc_sum5(&n);
memcpy(m, &n, sizeof(n));
return 0;
}
static int decode_unit3(SCPRContext *s, PixelModel3 *m, uint32_t code, uint32_t *value)
{
GetByteContext *gb = &s->gb;
RangeCoder *rc = &s->rc;
uint16_t a = 0, b = 0;
uint32_t param;
int type;
int ret;
type = m->type;
switch (type) {
case 0:
*value = bytestream2_get_byte(&s->gb);
m->type = 1;
m->size = 1;
m->symbols[0] = *value;
sync_code3(gb, rc);
break;
case 1:
*value = bytestream2_get_byte(&s->gb);
decode_static1(m, *value);
sync_code3(gb, rc);
break;
case 2:
*value = bytestream2_get_byte(&s->gb);
decode_static2(m, *value);
sync_code3(gb, rc);
break;
case 3:
*value = bytestream2_get_byte(&s->gb);
ret = decode_static3(m, *value);
if (ret < 0)
return AVERROR_INVALIDDATA;
sync_code3(gb, rc);
break;
case 4:
param = m->freqs[0] + m->freqs[1] + m->freqs[2] + m->freqs[3] + 256 - m->size;
if (!decode_adaptive45(m, code, value, &a, &b, &param, 4))
update_model4_to_5(m, *value);
decode3(gb, rc, a, b);
sync_code3(gb, rc);
break;
case 5:
if (!decode_adaptive45(m, code, value, &a, &b, &m->cntsum, 16))
update_model5_to_6(m, *value);
decode3(gb, rc, a, b);
sync_code3(gb, rc);
break;
case 6:
if (!decode_adaptive6(m, code, value, &a, &b)) {
ret = update_model6_to_7(m);
if (ret < 0)
return AVERROR_INVALIDDATA;
}
decode3(gb, rc, a, b);
sync_code3(gb, rc);
break;
case 7:
return decode_value3(s, 255, &m->cntsum,
m->freqs, m->freqs1,
m->cnts, m->dectab, value);
}
if (*value > 255)
return AVERROR_INVALIDDATA;
return 0;
}
static int decode_units3(SCPRContext * s, uint32_t *red,
uint32_t *green, uint32_t *blue,
int *cx, int *cx1)
{
RangeCoder *rc = &s->rc;
int ret;
ret = decode_unit3(s, &s->pixel_model3[0][*cx + *cx1], rc->code & 0xFFF, red);
if (ret < 0)
return ret;
*cx1 = (*cx << 6) & 0xFC0;
*cx = *red >> 2;
ret = decode_unit3(s, &s->pixel_model3[1][*cx + *cx1], rc->code & 0xFFF, green);
if (ret < 0)
return ret;
*cx1 = (*cx << 6) & 0xFC0;
*cx = *green >> 2;
ret = decode_unit3(s, &s->pixel_model3[2][*cx + *cx1], rc->code & 0xFFF, blue);
if (ret < 0)
return ret;
*cx1 = (*cx << 6) & 0xFC0;
*cx = *blue >> 2;
return 0;
}
static void init_rangecoder3(RangeCoder *rc, GetByteContext *gb)
{
rc->code = bytestream2_get_le32(gb);
rc->code1 = 0;
}
static int decompress_i3(AVCodecContext *avctx, uint32_t *dst, int linesize)
{
SCPRContext *s = avctx->priv_data;
GetByteContext *gb = &s->gb;
RangeCoder *rc = &s->rc;
int cx = 0, cx1 = 0, k = 0;
int run, off, y = 0, x = 0, ret;
uint32_t backstep = linesize - avctx->width;
uint32_t clr = 0, lx, ly, ptype, r, g, b;
bytestream2_skip(gb, 1);
init_rangecoder3(rc, gb);
reinit_tables3(s);
while (k < avctx->width + 1) {
ret = decode_units3(s, &r, &g, &b, &cx, &cx1);
if (ret < 0)
return ret;
ret = decode_value3(s, 255, &s->run_model3[0].cntsum,
s->run_model3[0].freqs[0],
s->run_model3[0].freqs[1],
s->run_model3[0].cnts,
s->run_model3[0].dectab, &run);
if (ret < 0)
return ret;
if (run <= 0)
return AVERROR_INVALIDDATA;
clr = (b << 16) + (g << 8) + r;
k += run;
while (run-- > 0) {
if (y >= avctx->height)
return AVERROR_INVALIDDATA;
dst[y * linesize + x] = clr;
lx = x;
ly = y;
x++;
if (x >= avctx->width) {
x = 0;
y++;
}
}
}
off = -linesize - 1;
ptype = 0;
while (x < avctx->width && y < avctx->height) {
ret = decode_value3(s, 5, &s->op_model3[ptype].cntsum,
s->op_model3[ptype].freqs[0],
s->op_model3[ptype].freqs[1],
s->op_model3[ptype].cnts,
s->op_model3[ptype].dectab, &ptype);
if (ret < 0)
return ret;
if (ptype == 0) {
ret = decode_units3(s, &r, &g, &b, &cx, &cx1);
if (ret < 0)
return ret;
clr = (b << 16) + (g << 8) + r;
}
if (ptype > 5)
return AVERROR_INVALIDDATA;
ret = decode_value3(s, 255, &s->run_model3[ptype].cntsum,
s->run_model3[ptype].freqs[0],
s->run_model3[ptype].freqs[1],
s->run_model3[ptype].cnts,
s->run_model3[ptype].dectab, &run);
if (ret < 0)
return ret;
if (run <= 0)
return AVERROR_INVALIDDATA;
ret = decode_run_i(avctx, ptype, run, &x, &y, clr,
dst, linesize, &lx, &ly,
backstep, off, &cx, &cx1);
if (ret < 0)
return ret;
}
return 0;
}
static int decompress_p3(AVCodecContext *avctx,
uint32_t *dst, int linesize,
uint32_t *prev, int plinesize)
{
SCPRContext *s = avctx->priv_data;
GetByteContext *gb = &s->gb;
int ret, temp, min, max, x, y, cx = 0, cx1 = 0;
int backstep = linesize - avctx->width;
int mvx = 0, mvy = 0;
if (bytestream2_get_byte(gb) == 0)
return 1;
init_rangecoder3(&s->rc, gb);
ret = decode_value3(s, 255, &s->range_model3.cntsum,
s->range_model3.freqs[0],
s->range_model3.freqs[1],
s->range_model3.cnts,
s->range_model3.dectab, &min);
ret |= decode_value3(s, 255, &s->range_model3.cntsum,
s->range_model3.freqs[0],
s->range_model3.freqs[1],
s->range_model3.cnts,
s->range_model3.dectab, &temp);
if (ret < 0)
return ret;
min += temp << 8;
ret |= decode_value3(s, 255, &s->range_model3.cntsum,
s->range_model3.freqs[0],
s->range_model3.freqs[1],
s->range_model3.cnts,
s->range_model3.dectab, &max);
ret |= decode_value3(s, 255, &s->range_model3.cntsum,
s->range_model3.freqs[0],
s->range_model3.freqs[1],
s->range_model3.cnts,
s->range_model3.dectab, &temp);
if (ret < 0)
return ret;
max += temp << 8;
if (min > max || min >= s->nbcount)
return AVERROR_INVALIDDATA;
memset(s->blocks, 0, sizeof(*s->blocks) * s->nbcount);
while (min <= max) {
int fill, count;
ret = decode_value3(s, 4, &s->fill_model3.cntsum,
s->fill_model3.freqs[0],
s->fill_model3.freqs[1],
s->fill_model3.cnts,
s->fill_model3.dectab, &fill);
ret |= decode_value3(s, 255, &s->count_model3.cntsum,
s->count_model3.freqs[0],
s->count_model3.freqs[1],
s->count_model3.cnts,
s->count_model3.dectab, &count);
if (ret < 0)
return ret;
if (count <= 0)
return AVERROR_INVALIDDATA;
while (min < s->nbcount && count-- > 0) {
s->blocks[min++] = fill;
}
}
ret = av_frame_copy(s->current_frame, s->last_frame);
if (ret < 0)
return ret;
for (y = 0; y < s->nby; y++) {
for (x = 0; x < s->nbx; x++) {
int sy1 = 0, sy2 = 16, sx1 = 0, sx2 = 16;
if (s->blocks[y * s->nbx + x] == 0)
continue;
if (((s->blocks[y * s->nbx + x] + 1) & 1) > 0) {
ret = decode_value3(s, 15, &s->sxy_model3[0].cntsum,
s->sxy_model3[0].freqs[0],
s->sxy_model3[0].freqs[1],
s->sxy_model3[0].cnts,
s->sxy_model3[0].dectab, &sx1);
ret |= decode_value3(s, 15, &s->sxy_model3[1].cntsum,
s->sxy_model3[1].freqs[0],
s->sxy_model3[1].freqs[1],
s->sxy_model3[1].cnts,
s->sxy_model3[1].dectab, &sy1);
ret |= decode_value3(s, 15, &s->sxy_model3[2].cntsum,
s->sxy_model3[2].freqs[0],
s->sxy_model3[2].freqs[1],
s->sxy_model3[2].cnts,
s->sxy_model3[2].dectab, &sx2);
ret |= decode_value3(s, 15, &s->sxy_model3[3].cntsum,
s->sxy_model3[3].freqs[0],
s->sxy_model3[3].freqs[1],
s->sxy_model3[3].cnts,
s->sxy_model3[3].dectab, &sy2);
if (ret < 0)
return ret;
sx2++;
sy2++;
}
if (((s->blocks[y * s->nbx + x] + 3) & 2) > 0) {
int i, a, b, c, j, by = y * 16, bx = x * 16;
uint32_t code;
a = s->rc.code & 0xFFF;
c = 1;
if (a < 0x800)
c = 0;
b = 2048;
if (!c)
b = 0;
code = a + ((s->rc.code >> 1) & 0xFFFFF800) - b;
while (code < 0x800000 && bytestream2_get_bytes_left(gb) > 0)
code = bytestream2_get_byteu(gb) | (code << 8);
s->rc.code = code;
sync_code3(gb, &s->rc);
if (!c) {
ret = decode_value3(s, 511, &s->mv_model3[0].cntsum,
s->mv_model3[0].freqs[0],
s->mv_model3[0].freqs[1],
s->mv_model3[0].cnts,
s->mv_model3[0].dectab, &mvx);
ret |= decode_value3(s, 511, &s->mv_model3[1].cntsum,
s->mv_model3[1].freqs[0],
s->mv_model3[1].freqs[1],
s->mv_model3[1].cnts,
s->mv_model3[1].dectab, &mvy);
if (ret < 0)
return ret;
mvx -= 256;
mvy -= 256;
}
if (by + mvy + sy1 < 0 || bx + mvx + sx1 < 0 ||
by + mvy + sy1 >= avctx->height || bx + mvx + sx1 >= avctx->width)
return AVERROR_INVALIDDATA;
for (i = 0; i < sy2 - sy1 && (by + sy1 + i) < avctx->height && (by + mvy + sy1 + i) < avctx->height; i++) {
for (j = 0; j < sx2 - sx1 && (bx + sx1 + j) < avctx->width && (bx + mvx + sx1 + j) < avctx->width; j++) {
dst[(by + i + sy1) * linesize + bx + sx1 + j] = prev[(by + mvy + sy1 + i) * plinesize + bx + sx1 + mvx + j];
}
}
} else {
int run, bx = x * 16 + sx1, by = y * 16 + sy1;
uint32_t clr, ptype = 0, r, g, b;
if (bx >= avctx->width)
return AVERROR_INVALIDDATA;
for (; by < y * 16 + sy2 && by < avctx->height;) {
ret = decode_value3(s, 5, &s->op_model3[ptype].cntsum,
s->op_model3[ptype].freqs[0],
s->op_model3[ptype].freqs[1],
s->op_model3[ptype].cnts,
s->op_model3[ptype].dectab, &ptype);
if (ret < 0)
return ret;
if (ptype == 0) {
ret = decode_units3(s, &r, &g, &b, &cx, &cx1);
if (ret < 0)
return ret;
clr = (b << 16) + (g << 8) + r;
}
if (ptype > 5)
return AVERROR_INVALIDDATA;
ret = decode_value3(s, 255, &s->run_model3[ptype].cntsum,
s->run_model3[ptype].freqs[0],
s->run_model3[ptype].freqs[1],
s->run_model3[ptype].cnts,
s->run_model3[ptype].dectab, &run);
if (ret < 0)
return ret;
if (run <= 0)
return AVERROR_INVALIDDATA;
ret = decode_run_p(avctx, ptype, run, x, y, clr,
dst, prev, linesize, plinesize, &bx, &by,
backstep, sx1, sx2, &cx, &cx1);
if (ret < 0)
return ret;
}
}
}
}
return 0;
}