// SPDX-License-Identifier: GPL-2.0-or-later
/* Linux driver for Philips webcam
Decompression for chipset version 2 et 3
(C) 2004-2006 Luc Saillard ([email protected])
NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
driver and thus may have bugs that are not present in the original version.
Please send bug reports and support requests to <[email protected]>.
The decompression routines have been implemented by reverse-engineering the
Nemosoft binary pwcx module. Caveat emptor.
*/
#include "pwc-timon.h"
#include "pwc-kiara.h"
#include "pwc-dec23.h"
#include <linux/string.h>
#include <linux/slab.h>
/*
* USE_LOOKUP_TABLE_TO_CLAMP
* 0: use a C version of this tests: { a<0?0:(a>255?255:a) }
* 1: use a faster lookup table for cpu with a big cache (intel)
*/
#define USE_LOOKUP_TABLE_TO_CLAMP 1
/*
* UNROLL_LOOP_FOR_COPYING_BLOCK
* 0: use a loop for a smaller code (but little slower)
* 1: when unrolling the loop, gcc produces some faster code (perhaps only
* valid for intel processor class). Activating this option, automatically
* activate USE_LOOKUP_TABLE_TO_CLAMP
*/
#define UNROLL_LOOP_FOR_COPY 1
#if UNROLL_LOOP_FOR_COPY
# undef USE_LOOKUP_TABLE_TO_CLAMP
# define USE_LOOKUP_TABLE_TO_CLAMP 1
#endif
static void build_subblock_pattern(struct pwc_dec23_private *pdec)
{
static const unsigned int initial_values[12] = {
-0x526500, -0x221200, 0x221200, 0x526500,
-0x3de200, 0x3de200,
-0x6db480, -0x2d5d00, 0x2d5d00, 0x6db480,
-0x12c200, 0x12c200
};
static const unsigned int values_derivated[12] = {
0xa4ca, 0x4424, -0x4424, -0xa4ca,
0x7bc4, -0x7bc4,
0xdb69, 0x5aba, -0x5aba, -0xdb69,
0x2584, -0x2584
};
unsigned int temp_values[12];
int i, j;
memcpy(temp_values, initial_values, sizeof(initial_values));
for (i = 0; i < 256; i++) {
for (j = 0; j < 12; j++) {
pdec->table_subblock[i][j] = temp_values[j];
temp_values[j] += values_derivated[j];
}
}
}
static void build_bit_powermask_table(struct pwc_dec23_private *pdec)
{
unsigned char *p;
unsigned int bit, byte, mask, val;
unsigned int bitpower = 1;
for (bit = 0; bit < 8; bit++) {
mask = bitpower - 1;
p = pdec->table_bitpowermask[bit];
for (byte = 0; byte < 256; byte++) {
val = (byte & mask);
if (byte & bitpower)
val = -val;
*p++ = val;
}
bitpower<<=1;
}
}
static void build_table_color(const unsigned int romtable[16][8],
unsigned char p0004[16][1024],
unsigned char p8004[16][256])
{
int compression_mode, j, k, bit, pw;
unsigned char *p0, *p8;
const unsigned int *r;
/* We have 16 compressions tables */
for (compression_mode = 0; compression_mode < 16; compression_mode++) {
p0 = p0004[compression_mode];
p8 = p8004[compression_mode];
r = romtable[compression_mode];
for (j = 0; j < 8; j++, r++, p0 += 128) {
for (k = 0; k < 16; k++) {
if (k == 0)
bit = 1;
else if (k >= 1 && k < 3)
bit = (r[0] >> 15) & 7;
else if (k >= 3 && k < 6)
bit = (r[0] >> 12) & 7;
else if (k >= 6 && k < 10)
bit = (r[0] >> 9) & 7;
else if (k >= 10 && k < 13)
bit = (r[0] >> 6) & 7;
else if (k >= 13 && k < 15)
bit = (r[0] >> 3) & 7;
else
bit = (r[0]) & 7;
if (k == 0)
*p8++ = 8;
else
*p8++ = j - bit;
*p8++ = bit;
pw = 1 << bit;
p0[k + 0x00] = (1 * pw) + 0x80;
p0[k + 0x10] = (2 * pw) + 0x80;
p0[k + 0x20] = (3 * pw) + 0x80;
p0[k + 0x30] = (4 * pw) + 0x80;
p0[k + 0x40] = (-1 * pw) + 0x80;
p0[k + 0x50] = (-2 * pw) + 0x80;
p0[k + 0x60] = (-3 * pw) + 0x80;
p0[k + 0x70] = (-4 * pw) + 0x80;
} /* end of for (k=0; k<16; k++, p8++) */
} /* end of for (j=0; j<8; j++ , table++) */
} /* end of foreach compression_mode */
}
/*
*
*/
static void fill_table_dc00_d800(struct pwc_dec23_private *pdec)
{
#define SCALEBITS 15
#define ONE_HALF (1UL << (SCALEBITS - 1))
int i;
unsigned int offset1 = ONE_HALF;
unsigned int offset2 = 0x0000;
for (i=0; i<256; i++) {
pdec->table_dc00[i] = offset1 & ~(ONE_HALF);
pdec->table_d800[i] = offset2;
offset1 += 0x7bc4;
offset2 += 0x7bc4;
}
}
/*
* To decode the stream:
* if look_bits(2) == 0: # op == 2 in the lookup table
* skip_bits(2)
* end of the stream
* elif look_bits(3) == 7: # op == 1 in the lookup table
* skip_bits(3)
* yyyy = get_bits(4)
* xxxx = get_bits(8)
* else: # op == 0 in the lookup table
* skip_bits(x)
*
* For speedup processing, we build a lookup table and we takes the first 6 bits.
*
* struct {
* unsigned char op; // operation to execute
* unsigned char bits; // bits use to perform operation
* unsigned char offset1; // offset to add to access in the table_0004 % 16
* unsigned char offset2; // offset to add to access in the table_0004
* }
*
* How to build this table ?
* op == 2 when (i%4)==0
* op == 1 when (i%8)==7
* op == 0 otherwise
*
*/
static const unsigned char hash_table_ops[64*4] = {
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x10,
0x00, 0x06, 0x01, 0x30,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x01, 0x20,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x50,
0x00, 0x05, 0x02, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x03, 0x00,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x10,
0x00, 0x06, 0x02, 0x10,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x01, 0x60,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x50,
0x00, 0x05, 0x02, 0x40,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x03, 0x40,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x10,
0x00, 0x06, 0x01, 0x70,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x01, 0x20,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x50,
0x00, 0x05, 0x02, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x03, 0x00,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x10,
0x00, 0x06, 0x02, 0x50,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x01, 0x60,
0x01, 0x00, 0x00, 0x00,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x00,
0x00, 0x04, 0x01, 0x50,
0x00, 0x05, 0x02, 0x40,
0x02, 0x00, 0x00, 0x00,
0x00, 0x03, 0x01, 0x40,
0x00, 0x05, 0x03, 0x40,
0x01, 0x00, 0x00, 0x00
};
/*
*
*/
static const unsigned int MulIdx[16][16] = {
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,},
{0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3,},
{0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3,},
{4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 4, 4, 4, 4,},
{6, 7, 8, 9, 7, 10, 11, 8, 8, 11, 10, 7, 9, 8, 7, 6,},
{4, 5, 5, 4, 4, 5, 5, 4, 4, 5, 5, 4, 4, 5, 5, 4,},
{1, 3, 0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3, 0, 2,},
{0, 3, 3, 0, 1, 2, 2, 1, 2, 1, 1, 2, 3, 0, 0, 3,},
{0, 1, 2, 3, 3, 2, 1, 0, 3, 2, 1, 0, 0, 1, 2, 3,},
{1, 1, 1, 1, 3, 3, 3, 3, 0, 0, 0, 0, 2, 2, 2, 2,},
{7, 10, 11, 8, 9, 8, 7, 6, 6, 7, 8, 9, 8, 11, 10, 7,},
{4, 5, 5, 4, 5, 4, 4, 5, 5, 4, 4, 5, 4, 5, 5, 4,},
{7, 9, 6, 8, 10, 8, 7, 11, 11, 7, 8, 10, 8, 6, 9, 7,},
{1, 3, 0, 2, 2, 0, 3, 1, 2, 0, 3, 1, 1, 3, 0, 2,},
{1, 2, 2, 1, 3, 0, 0, 3, 0, 3, 3, 0, 2, 1, 1, 2,},
{10, 8, 7, 11, 8, 6, 9, 7, 7, 9, 6, 8, 11, 7, 8, 10}
};
#if USE_LOOKUP_TABLE_TO_CLAMP
#define MAX_OUTER_CROP_VALUE (512)
static unsigned char pwc_crop_table[256 + 2*MAX_OUTER_CROP_VALUE];
#define CLAMP(x) (pwc_crop_table[MAX_OUTER_CROP_VALUE+(x)])
#else
#define CLAMP(x) ((x)>255?255:((x)<0?0:x))
#endif
/* If the type or the command change, we rebuild the lookup table */
void pwc_dec23_init(struct pwc_device *pdev, const unsigned char *cmd)
{
int flags, version, shift, i;
struct pwc_dec23_private *pdec = &pdev->dec23;
mutex_init(&pdec->lock);
if (pdec->last_cmd_valid && pdec->last_cmd == cmd[2])
return;
if (DEVICE_USE_CODEC3(pdev->type)) {
flags = cmd[2] & 0x18;
if (flags == 8)
pdec->nbits = 7; /* More bits, mean more bits to encode the stream, but better quality */
else if (flags == 0x10)
pdec->nbits = 8;
else
pdec->nbits = 6;
version = cmd[2] >> 5;
build_table_color(KiaraRomTable[version][0], pdec->table_0004_pass1, pdec->table_8004_pass1);
build_table_color(KiaraRomTable[version][1], pdec->table_0004_pass2, pdec->table_8004_pass2);
} else {
flags = cmd[2] & 6;
if (flags == 2)
pdec->nbits = 7;
else if (flags == 4)
pdec->nbits = 8;
else
pdec->nbits = 6;
version = cmd[2] >> 3;
build_table_color(TimonRomTable[version][0], pdec->table_0004_pass1, pdec->table_8004_pass1);
build_table_color(TimonRomTable[version][1], pdec->table_0004_pass2, pdec->table_8004_pass2);
}
/* Information can be coded on a variable number of bits but never less than 8 */
shift = 8 - pdec->nbits;
pdec->scalebits = SCALEBITS - shift;
pdec->nbitsmask = 0xFF >> shift;
fill_table_dc00_d800(pdec);
build_subblock_pattern(pdec);
build_bit_powermask_table(pdec);
#if USE_LOOKUP_TABLE_TO_CLAMP
/* Build the static table to clamp value [0-255] */
for (i=0;i<MAX_OUTER_CROP_VALUE;i++)
pwc_crop_table[i] = 0;
for (i=0; i<256; i++)
pwc_crop_table[MAX_OUTER_CROP_VALUE+i] = i;
for (i=0; i<MAX_OUTER_CROP_VALUE; i++)
pwc_crop_table[MAX_OUTER_CROP_VALUE+256+i] = 255;
#endif
pdec->last_cmd = cmd[2];
pdec->last_cmd_valid = 1;
}
/*
* Copy the 4x4 image block to Y plane buffer
*/
static void copy_image_block_Y(const int *src, unsigned char *dst, unsigned int bytes_per_line, unsigned int scalebits)
{
#if UNROLL_LOOP_FOR_COPY
const unsigned char *cm = pwc_crop_table+MAX_OUTER_CROP_VALUE;
const int *c = src;
unsigned char *d = dst;
*d++ = cm[c[0] >> scalebits];
*d++ = cm[c[1] >> scalebits];
*d++ = cm[c[2] >> scalebits];
*d++ = cm[c[3] >> scalebits];
d = dst + bytes_per_line;
*d++ = cm[c[4] >> scalebits];
*d++ = cm[c[5] >> scalebits];
*d++ = cm[c[6] >> scalebits];
*d++ = cm[c[7] >> scalebits];
d = dst + bytes_per_line*2;
*d++ = cm[c[8] >> scalebits];
*d++ = cm[c[9] >> scalebits];
*d++ = cm[c[10] >> scalebits];
*d++ = cm[c[11] >> scalebits];
d = dst + bytes_per_line*3;
*d++ = cm[c[12] >> scalebits];
*d++ = cm[c[13] >> scalebits];
*d++ = cm[c[14] >> scalebits];
*d++ = cm[c[15] >> scalebits];
#else
int i;
const int *c = src;
unsigned char *d = dst;
for (i = 0; i < 4; i++, c++)
*d++ = CLAMP((*c) >> scalebits);
d = dst + bytes_per_line;
for (i = 0; i < 4; i++, c++)
*d++ = CLAMP((*c) >> scalebits);
d = dst + bytes_per_line*2;
for (i = 0; i < 4; i++, c++)
*d++ = CLAMP((*c) >> scalebits);
d = dst + bytes_per_line*3;
for (i = 0; i < 4; i++, c++)
*d++ = CLAMP((*c) >> scalebits);
#endif
}
/*
* Copy the 4x4 image block to a CrCb plane buffer
*
*/
static void copy_image_block_CrCb(const int *src, unsigned char *dst, unsigned int bytes_per_line, unsigned int scalebits)
{
#if UNROLL_LOOP_FOR_COPY
/* Unroll all loops */
const unsigned char *cm = pwc_crop_table+MAX_OUTER_CROP_VALUE;
const int *c = src;
unsigned char *d = dst;
*d++ = cm[c[0] >> scalebits];
*d++ = cm[c[4] >> scalebits];
*d++ = cm[c[1] >> scalebits];
*d++ = cm[c[5] >> scalebits];
*d++ = cm[c[2] >> scalebits];
*d++ = cm[c[6] >> scalebits];
*d++ = cm[c[3] >> scalebits];
*d++ = cm[c[7] >> scalebits];
d = dst + bytes_per_line;
*d++ = cm[c[12] >> scalebits];
*d++ = cm[c[8] >> scalebits];
*d++ = cm[c[13] >> scalebits];
*d++ = cm[c[9] >> scalebits];
*d++ = cm[c[14] >> scalebits];
*d++ = cm[c[10] >> scalebits];
*d++ = cm[c[15] >> scalebits];
*d++ = cm[c[11] >> scalebits];
#else
int i;
const int *c1 = src;
const int *c2 = src + 4;
unsigned char *d = dst;
for (i = 0; i < 4; i++, c1++, c2++) {
*d++ = CLAMP((*c1) >> scalebits);
*d++ = CLAMP((*c2) >> scalebits);
}
c1 = src + 12;
d = dst + bytes_per_line;
for (i = 0; i < 4; i++, c1++, c2++) {
*d++ = CLAMP((*c1) >> scalebits);
*d++ = CLAMP((*c2) >> scalebits);
}
#endif
}
/*
* To manage the stream, we keep bits in a 32 bits register.
* fill_nbits(n): fill the reservoir with at least n bits
* skip_bits(n): discard n bits from the reservoir
* get_bits(n): fill the reservoir, returns the first n bits and discard the
* bits from the reservoir.
* __get_nbits(n): faster version of get_bits(n), but asumes that the reservoir
* contains at least n bits. bits returned is discarded.
*/
#define fill_nbits(pdec, nbits_wanted) do { \
while (pdec->nbits_in_reservoir<(nbits_wanted)) \
{ \
pdec->reservoir |= (*(pdec->stream)++) << (pdec->nbits_in_reservoir); \
pdec->nbits_in_reservoir += 8; \
} \
} while(0);
#define skip_nbits(pdec, nbits_to_skip) do { \
pdec->reservoir >>= (nbits_to_skip); \
pdec->nbits_in_reservoir -= (nbits_to_skip); \
} while(0);
#define get_nbits(pdec, nbits_wanted, result) do { \
fill_nbits(pdec, nbits_wanted); \
result = (pdec->reservoir) & ((1U<<(nbits_wanted))-1); \
skip_nbits(pdec, nbits_wanted); \
} while(0);
#define __get_nbits(pdec, nbits_wanted, result) do { \
result = (pdec->reservoir) & ((1U<<(nbits_wanted))-1); \
skip_nbits(pdec, nbits_wanted); \
} while(0);
#define look_nbits(pdec, nbits_wanted) \
((pdec->reservoir) & ((1U<<(nbits_wanted))-1))
/*
* Decode a 4x4 pixel block
*/
static void decode_block(struct pwc_dec23_private *pdec,
const unsigned char *ptable0004,
const unsigned char *ptable8004)
{
unsigned int primary_color;
unsigned int channel_v, offset1, op;
int i;
fill_nbits(pdec, 16);
__get_nbits(pdec, pdec->nbits, primary_color);
if (look_nbits(pdec,2) == 0) {
skip_nbits(pdec, 2);
/* Very simple, the color is the same for all pixels of the square */
for (i = 0; i < 16; i++)
pdec->temp_colors[i] = pdec->table_dc00[primary_color];
return;
}
/* This block is encoded with small pattern */
for (i = 0; i < 16; i++)
pdec->temp_colors[i] = pdec->table_d800[primary_color];
__get_nbits(pdec, 3, channel_v);
channel_v = ((channel_v & 1) << 2) | (channel_v & 2) | ((channel_v & 4) >> 2);
ptable0004 += (channel_v * 128);
ptable8004 += (channel_v * 32);
offset1 = 0;
do
{
unsigned int htable_idx, rows = 0;
const unsigned int *block;
/* [ zzzz y x x ]
* xx == 00 :=> end of the block def, remove the two bits from the stream
* yxx == 111
* yxx == any other value
*
*/
fill_nbits(pdec, 16);
htable_idx = look_nbits(pdec, 6);
op = hash_table_ops[htable_idx * 4];
if (op == 2) {
skip_nbits(pdec, 2);
} else if (op == 1) {
/* 15bits [ xxxx xxxx yyyy 111 ]
* yyy => offset in the table8004
* xxx => offset in the tabled004 (tree)
*/
unsigned int mask, shift;
unsigned int nbits, col1;
unsigned int yyyy;
skip_nbits(pdec, 3);
/* offset1 += yyyy */
__get_nbits(pdec, 4, yyyy);
offset1 += 1 + yyyy;
offset1 &= 0x0F;
nbits = ptable8004[offset1 * 2];
/* col1 = xxxx xxxx */
__get_nbits(pdec, nbits+1, col1);
/* Bit mask table */
mask = pdec->table_bitpowermask[nbits][col1];
shift = ptable8004[offset1 * 2 + 1];
rows = ((mask << shift) + 0x80) & 0xFF;
block = pdec->table_subblock[rows];
for (i = 0; i < 16; i++)
pdec->temp_colors[i] += block[MulIdx[offset1][i]];
} else {
/* op == 0
* offset1 is coded on 3 bits
*/
unsigned int shift;
offset1 += hash_table_ops [htable_idx * 4 + 2];
offset1 &= 0x0F;
rows = ptable0004[offset1 + hash_table_ops [htable_idx * 4 + 3]];
block = pdec->table_subblock[rows];
for (i = 0; i < 16; i++)
pdec->temp_colors[i] += block[MulIdx[offset1][i]];
shift = hash_table_ops[htable_idx * 4 + 1];
skip_nbits(pdec, shift);
}
} while (op != 2);
}
static void DecompressBand23(struct pwc_dec23_private *pdec,
const unsigned char *rawyuv,
unsigned char *planar_y,
unsigned char *planar_u,
unsigned char *planar_v,
unsigned int compressed_image_width,
unsigned int real_image_width)
{
int compression_index, nblocks;
const unsigned char *ptable0004;
const unsigned char *ptable8004;
pdec->reservoir = 0;
pdec->nbits_in_reservoir = 0;
pdec->stream = rawyuv + 1; /* The first byte of the stream is skipped */
get_nbits(pdec, 4, compression_index);
/* pass 1: uncompress Y component */
nblocks = compressed_image_width / 4;
ptable0004 = pdec->table_0004_pass1[compression_index];
ptable8004 = pdec->table_8004_pass1[compression_index];
/* Each block decode a square of 4x4 */
while (nblocks) {
decode_block(pdec, ptable0004, ptable8004);
copy_image_block_Y(pdec->temp_colors, planar_y, real_image_width, pdec->scalebits);
planar_y += 4;
nblocks--;
}
/* pass 2: uncompress UV component */
nblocks = compressed_image_width / 8;
ptable0004 = pdec->table_0004_pass2[compression_index];
ptable8004 = pdec->table_8004_pass2[compression_index];
/* Each block decode a square of 4x4 */
while (nblocks) {
decode_block(pdec, ptable0004, ptable8004);
copy_image_block_CrCb(pdec->temp_colors, planar_u, real_image_width/2, pdec->scalebits);
decode_block(pdec, ptable0004, ptable8004);
copy_image_block_CrCb(pdec->temp_colors, planar_v, real_image_width/2, pdec->scalebits);
planar_v += 8;
planar_u += 8;
nblocks -= 2;
}
}
/**
* pwc_dec23_decompress - Uncompress a pwc23 buffer.
* @pdev: pointer to pwc device's internal struct
* @src: raw data
* @dst: image output
*/
void pwc_dec23_decompress(struct pwc_device *pdev,
const void *src,
void *dst)
{
int bandlines_left, bytes_per_block;
struct pwc_dec23_private *pdec = &pdev->dec23;
/* YUV420P image format */
unsigned char *pout_planar_y;
unsigned char *pout_planar_u;
unsigned char *pout_planar_v;
unsigned int plane_size;
mutex_lock(&pdec->lock);
bandlines_left = pdev->height / 4;
bytes_per_block = pdev->width * 4;
plane_size = pdev->height * pdev->width;
pout_planar_y = dst;
pout_planar_u = dst + plane_size;
pout_planar_v = dst + plane_size + plane_size / 4;
while (bandlines_left--) {
DecompressBand23(pdec, src,
pout_planar_y, pout_planar_u, pout_planar_v,
pdev->width, pdev->width);
src += pdev->vbandlength;
pout_planar_y += bytes_per_block;
pout_planar_u += pdev->width;
pout_planar_v += pdev->width;
}
mutex_unlock(&pdec->lock);
}
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