cregit-Linux how code gets into the kernel

Release 4.11 drivers/media/usb/pwc/pwc-dec23.c

/* Linux driver for Philips webcam
   Decompression for chipset version 2 et 3
   (C) 2004-2006  Luc Saillard (luc@saillard.org)

   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 <luc@saillard.org>.
   The decompression routines have been implemented by reverse-engineering the
   Nemosoft binary pwcx module. Caveat emptor.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*/

#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, automaticaly
 *   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]; } } }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard172100.00%1100.00%
Total172100.00%1100.00%


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; } }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard106100.00%1100.00%
Total106100.00%1100.00%


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 */ }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard438100.00%1100.00%
Total438100.00%1100.00%

/* * */
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; } }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard80100.00%1100.00%
Total80100.00%1100.00%

/* * 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); } /* Informations 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; }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard32887.00%120.00%
Hans de Goede4913.00%480.00%
Total377100.00%5100.00%

/* * 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 }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard460100.00%1100.00%
Total460100.00%1100.00%

/* * 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 }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard422100.00%1100.00%
Total422100.00%1100.00%

/* * 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); }

Contributors

PersonTokensPropCommitsCommitProp
Hans de Goede35871.03%150.00%
Luc Saillard14628.97%150.00%
Total504100.00%2100.00%


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; } }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard21486.99%150.00%
Hans de Goede3213.01%150.00%
Total246100.00%2100.00%

/** * * Uncompress a pwc23 buffer. * * 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); }

Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard10160.84%120.00%
Hans de Goede6539.16%480.00%
Total166100.00%5100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Luc Saillard362886.63%112.50%
Hans de Goede55713.30%675.00%
Tejun Heo30.07%112.50%
Total4188100.00%8100.00%
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