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ffmpeg/libavcodec/truemotion1.c
Anton Khirnov c918e08b9c truemotion1: make sure index does not go out of bounds 
Fixes invalid reads.
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC:libav-stable@libav.org
2013-11-21 20:58:08 +01:00

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/*
* Duck TrueMotion 1.0 Decoder
* Copyright (C) 2003 Alex Beregszaszi & Mike Melanson
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Duck TrueMotion v1 Video Decoder by
* Alex Beregszaszi and
* Mike Melanson (melanson@pcisys.net)
*
* The TrueMotion v1 decoder presently only decodes 16-bit TM1 data and
* outputs RGB555 (or RGB565) data. 24-bit TM1 data is not supported yet.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "avcodec.h"
#include "internal.h"
#include "libavutil/imgutils.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/mem.h"
#include "truemotion1data.h"
typedef struct TrueMotion1Context {
AVCodecContext *avctx;
AVFrame *frame;
const uint8_t *buf;
int size;
const uint8_t *mb_change_bits;
int mb_change_bits_row_size;
const uint8_t *index_stream;
int index_stream_size;
int flags;
int x, y, w, h;
uint32_t y_predictor_table[1024];
uint32_t c_predictor_table[1024];
uint32_t fat_y_predictor_table[1024];
uint32_t fat_c_predictor_table[1024];
int compression;
int block_type;
int block_width;
int block_height;
int16_t ydt[8];
int16_t cdt[8];
int16_t fat_ydt[8];
int16_t fat_cdt[8];
int last_deltaset, last_vectable;
unsigned int *vert_pred;
int vert_pred_size;
} TrueMotion1Context;
#define FLAG_SPRITE 32
#define FLAG_KEYFRAME 16
#define FLAG_INTERFRAME 8
#define FLAG_INTERPOLATED 4
struct frame_header {
uint8_t header_size;
uint8_t compression;
uint8_t deltaset;
uint8_t vectable;
uint16_t ysize;
uint16_t xsize;
uint16_t checksum;
uint8_t version;
uint8_t header_type;
uint8_t flags;
uint8_t control;
uint16_t xoffset;
uint16_t yoffset;
uint16_t width;
uint16_t height;
};
#define ALGO_NOP 0
#define ALGO_RGB16V 1
#define ALGO_RGB16H 2
#define ALGO_RGB24H 3
/* these are the various block sizes that can occupy a 4x4 block */
#define BLOCK_2x2 0
#define BLOCK_2x4 1
#define BLOCK_4x2 2
#define BLOCK_4x4 3
typedef struct comp_types {
int algorithm;
int block_width; // vres
int block_height; // hres
int block_type;
} comp_types;
/* { valid for metatype }, algorithm, num of deltas, vert res, horiz res */
static const comp_types compression_types[17] = {
{ ALGO_NOP, 0, 0, 0 },
{ ALGO_RGB16V, 4, 4, BLOCK_4x4 },
{ ALGO_RGB16H, 4, 4, BLOCK_4x4 },
{ ALGO_RGB16V, 4, 2, BLOCK_4x2 },
{ ALGO_RGB16H, 4, 2, BLOCK_4x2 },
{ ALGO_RGB16V, 2, 4, BLOCK_2x4 },
{ ALGO_RGB16H, 2, 4, BLOCK_2x4 },
{ ALGO_RGB16V, 2, 2, BLOCK_2x2 },
{ ALGO_RGB16H, 2, 2, BLOCK_2x2 },
{ ALGO_NOP, 4, 4, BLOCK_4x4 },
{ ALGO_RGB24H, 4, 4, BLOCK_4x4 },
{ ALGO_NOP, 4, 2, BLOCK_4x2 },
{ ALGO_RGB24H, 4, 2, BLOCK_4x2 },
{ ALGO_NOP, 2, 4, BLOCK_2x4 },
{ ALGO_RGB24H, 2, 4, BLOCK_2x4 },
{ ALGO_NOP, 2, 2, BLOCK_2x2 },
{ ALGO_RGB24H, 2, 2, BLOCK_2x2 }
};
static void select_delta_tables(TrueMotion1Context *s, int delta_table_index)
{
int i;
if (delta_table_index > 3)
return;
memcpy(s->ydt, ydts[delta_table_index], 8 * sizeof(int16_t));
memcpy(s->cdt, cdts[delta_table_index], 8 * sizeof(int16_t));
memcpy(s->fat_ydt, fat_ydts[delta_table_index], 8 * sizeof(int16_t));
memcpy(s->fat_cdt, fat_cdts[delta_table_index], 8 * sizeof(int16_t));
/* Y skinny deltas need to be halved for some reason; maybe the
* skinny Y deltas should be modified */
for (i = 0; i < 8; i++)
{
/* drop the lsb before dividing by 2-- net effect: round down
* when dividing a negative number (e.g., -3/2 = -2, not -1) */
s->ydt[i] &= 0xFFFE;
s->ydt[i] /= 2;
}
}
#if HAVE_BIGENDIAN
static int make_ydt15_entry(int p2, int p1, int16_t *ydt)
#else
static int make_ydt15_entry(int p1, int p2, int16_t *ydt)
#endif
{
int lo, hi;
lo = ydt[p1];
lo += (lo << 5) + (lo << 10);
hi = ydt[p2];
hi += (hi << 5) + (hi << 10);
return (lo + (hi << 16)) << 1;
}
static int make_cdt15_entry(int p1, int p2, int16_t *cdt)
{
int r, b, lo;
b = cdt[p2];
r = cdt[p1] << 10;
lo = b + r;
return (lo + (lo << 16)) << 1;
}
#if HAVE_BIGENDIAN
static int make_ydt16_entry(int p2, int p1, int16_t *ydt)
#else
static int make_ydt16_entry(int p1, int p2, int16_t *ydt)
#endif
{
int lo, hi;
lo = ydt[p1];
lo += (lo << 6) + (lo << 11);
hi = ydt[p2];
hi += (hi << 6) + (hi << 11);
return (lo + (hi << 16)) << 1;
}
static int make_cdt16_entry(int p1, int p2, int16_t *cdt)
{
int r, b, lo;
b = cdt[p2];
r = cdt[p1] << 11;
lo = b + r;
return (lo + (lo << 16)) << 1;
}
static int make_ydt24_entry(int p1, int p2, int16_t *ydt)
{
int lo, hi;
lo = ydt[p1];
hi = ydt[p2];
return (lo + (hi << 8) + (hi << 16)) << 1;
}
static int make_cdt24_entry(int p1, int p2, int16_t *cdt)
{
int r, b;
b = cdt[p2];
r = cdt[p1]<<16;
return (b+r) << 1;
}
static void gen_vector_table15(TrueMotion1Context *s, const uint8_t *sel_vector_table)
{
int len, i, j;
unsigned char delta_pair;
for (i = 0; i < 1024; i += 4)
{
len = *sel_vector_table++ / 2;
for (j = 0; j < len; j++)
{
delta_pair = *sel_vector_table++;
s->y_predictor_table[i+j] = 0xfffffffe &
make_ydt15_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
s->c_predictor_table[i+j] = 0xfffffffe &
make_cdt15_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
}
s->y_predictor_table[i+(j-1)] |= 1;
s->c_predictor_table[i+(j-1)] |= 1;
}
}
static void gen_vector_table16(TrueMotion1Context *s, const uint8_t *sel_vector_table)
{
int len, i, j;
unsigned char delta_pair;
for (i = 0; i < 1024; i += 4)
{
len = *sel_vector_table++ / 2;
for (j = 0; j < len; j++)
{
delta_pair = *sel_vector_table++;
s->y_predictor_table[i+j] = 0xfffffffe &
make_ydt16_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
s->c_predictor_table[i+j] = 0xfffffffe &
make_cdt16_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
}
s->y_predictor_table[i+(j-1)] |= 1;
s->c_predictor_table[i+(j-1)] |= 1;
}
}
static void gen_vector_table24(TrueMotion1Context *s, const uint8_t *sel_vector_table)
{
int len, i, j;
unsigned char delta_pair;
for (i = 0; i < 1024; i += 4)
{
len = *sel_vector_table++ / 2;
for (j = 0; j < len; j++)
{
delta_pair = *sel_vector_table++;
s->y_predictor_table[i+j] = 0xfffffffe &
make_ydt24_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
s->c_predictor_table[i+j] = 0xfffffffe &
make_cdt24_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
s->fat_y_predictor_table[i+j] = 0xfffffffe &
make_ydt24_entry(delta_pair >> 4, delta_pair & 0xf, s->fat_ydt);
s->fat_c_predictor_table[i+j] = 0xfffffffe &
make_cdt24_entry(delta_pair >> 4, delta_pair & 0xf, s->fat_cdt);
}
s->y_predictor_table[i+(j-1)] |= 1;
s->c_predictor_table[i+(j-1)] |= 1;
s->fat_y_predictor_table[i+(j-1)] |= 1;
s->fat_c_predictor_table[i+(j-1)] |= 1;
}
}
/* Returns the number of bytes consumed from the bytestream. Returns -1 if
* there was an error while decoding the header */
static int truemotion1_decode_header(TrueMotion1Context *s)
{
int i, ret;
int width_shift = 0;
int new_pix_fmt;
struct frame_header header;
uint8_t header_buffer[128] = { 0 }; /* logical maximum size of the header */
const uint8_t *sel_vector_table;
header.header_size = ((s->buf[0] >> 5) | (s->buf[0] << 3)) & 0x7f;
if (s->buf[0] < 0x10)
{
av_log(s->avctx, AV_LOG_ERROR, "invalid header size (%d)\n", s->buf[0]);
return AVERROR_INVALIDDATA;
}
/* unscramble the header bytes with a XOR operation */
for (i = 1; i < header.header_size; i++)
header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];
header.compression = header_buffer[0];
header.deltaset = header_buffer[1];
header.vectable = header_buffer[2];
header.ysize = AV_RL16(&header_buffer[3]);
header.xsize = AV_RL16(&header_buffer[5]);
header.checksum = AV_RL16(&header_buffer[7]);
header.version = header_buffer[9];
header.header_type = header_buffer[10];
header.flags = header_buffer[11];
header.control = header_buffer[12];
/* Version 2 */
if (header.version >= 2)
{
if (header.header_type > 3)
{
av_log(s->avctx, AV_LOG_ERROR, "invalid header type (%d)\n", header.header_type);
return AVERROR_INVALIDDATA;
} else if ((header.header_type == 2) || (header.header_type == 3)) {
s->flags = header.flags;
if (!(s->flags & FLAG_INTERFRAME))
s->flags |= FLAG_KEYFRAME;
} else
s->flags = FLAG_KEYFRAME;
} else /* Version 1 */
s->flags = FLAG_KEYFRAME;
if (s->flags & FLAG_SPRITE) {
avpriv_request_sample(s->avctx, "Frame with sprite");
/* FIXME header.width, height, xoffset and yoffset aren't initialized */
return AVERROR_PATCHWELCOME;
} else {
s->w = header.xsize;
s->h = header.ysize;
if (header.header_type < 2) {
if ((s->w < 213) && (s->h >= 176))
{
s->flags |= FLAG_INTERPOLATED;
avpriv_request_sample(s->avctx, "Interpolated frame");
}
}
}
if (header.compression >= 17) {
av_log(s->avctx, AV_LOG_ERROR, "invalid compression type (%d)\n", header.compression);
return AVERROR_INVALIDDATA;
}
if ((header.deltaset != s->last_deltaset) ||
(header.vectable != s->last_vectable))
select_delta_tables(s, header.deltaset);
if ((header.compression & 1) && header.header_type)
sel_vector_table = pc_tbl2;
else {
if (header.vectable > 0 && header.vectable < 4)
sel_vector_table = tables[header.vectable - 1];
else {
av_log(s->avctx, AV_LOG_ERROR, "invalid vector table id (%d)\n", header.vectable);
return AVERROR_INVALIDDATA;
}
}
if (compression_types[header.compression].algorithm == ALGO_RGB24H) {
new_pix_fmt = AV_PIX_FMT_RGB32;
width_shift = 1;
} else
new_pix_fmt = AV_PIX_FMT_RGB555; // RGB565 is supported as well
s->w >>= width_shift;
if (s->w != s->avctx->width || s->h != s->avctx->height ||
new_pix_fmt != s->avctx->pix_fmt) {
av_frame_unref(s->frame);
s->avctx->sample_aspect_ratio = (AVRational){ 1 << width_shift, 1 };
s->avctx->pix_fmt = new_pix_fmt;
if ((ret = ff_set_dimensions(s->avctx, s->w, s->h)) < 0)
return ret;
av_fast_malloc(&s->vert_pred, &s->vert_pred_size, s->avctx->width * sizeof(unsigned int));
}
/* There is 1 change bit per 4 pixels, so each change byte represents
* 32 pixels; divide width by 4 to obtain the number of change bits and
* then round up to the nearest byte. */
s->mb_change_bits_row_size = ((s->avctx->width >> (2 - width_shift)) + 7) >> 3;
if ((header.deltaset != s->last_deltaset) || (header.vectable != s->last_vectable))
{
if (compression_types[header.compression].algorithm == ALGO_RGB24H)
gen_vector_table24(s, sel_vector_table);
else
if (s->avctx->pix_fmt == AV_PIX_FMT_RGB555)
gen_vector_table15(s, sel_vector_table);
else
gen_vector_table16(s, sel_vector_table);
}
/* set up pointers to the other key data chunks */
s->mb_change_bits = s->buf + header.header_size;
if (s->flags & FLAG_KEYFRAME) {
/* no change bits specified for a keyframe; only index bytes */
s->index_stream = s->mb_change_bits;
} else {
/* one change bit per 4x4 block */
s->index_stream = s->mb_change_bits +
(s->mb_change_bits_row_size * (s->avctx->height >> 2));
}
s->index_stream_size = s->size - (s->index_stream - s->buf);
s->last_deltaset = header.deltaset;
s->last_vectable = header.vectable;
s->compression = header.compression;
s->block_width = compression_types[header.compression].block_width;
s->block_height = compression_types[header.compression].block_height;
s->block_type = compression_types[header.compression].block_type;
if (s->avctx->debug & FF_DEBUG_PICT_INFO)
av_log(s->avctx, AV_LOG_INFO, "tables: %d / %d c:%d %dx%d t:%d %s%s%s%s\n",
s->last_deltaset, s->last_vectable, s->compression, s->block_width,
s->block_height, s->block_type,
s->flags & FLAG_KEYFRAME ? " KEY" : "",
s->flags & FLAG_INTERFRAME ? " INTER" : "",
s->flags & FLAG_SPRITE ? " SPRITE" : "",
s->flags & FLAG_INTERPOLATED ? " INTERPOL" : "");
return header.header_size;
}
static av_cold int truemotion1_decode_init(AVCodecContext *avctx)
{
TrueMotion1Context *s = avctx->priv_data;
s->avctx = avctx;
// FIXME: it may change ?
// if (avctx->bits_per_sample == 24)
// avctx->pix_fmt = AV_PIX_FMT_RGB24;
// else
// avctx->pix_fmt = AV_PIX_FMT_RGB555;
s->frame = av_frame_alloc();
if (!s->frame)
return AVERROR(ENOMEM);
/* there is a vertical predictor for each pixel in a line; each vertical
* predictor is 0 to start with */
av_fast_malloc(&s->vert_pred, &s->vert_pred_size, s->avctx->width * sizeof(unsigned int));
return 0;
}
/*
Block decoding order:
dxi: Y-Y
dxic: Y-C-Y
dxic2: Y-C-Y-C
hres,vres,i,i%vres (0 < i < 4)
2x2 0: 0 dxic2
2x2 1: 1 dxi
2x2 2: 0 dxic2
2x2 3: 1 dxi
2x4 0: 0 dxic2
2x4 1: 1 dxi
2x4 2: 2 dxi
2x4 3: 3 dxi
4x2 0: 0 dxic
4x2 1: 1 dxi
4x2 2: 0 dxic
4x2 3: 1 dxi
4x4 0: 0 dxic
4x4 1: 1 dxi
4x4 2: 2 dxi
4x4 3: 3 dxi
*/
#define GET_NEXT_INDEX() \
{\
if (index_stream_index >= s->index_stream_size) { \
av_log(s->avctx, AV_LOG_INFO, " help! truemotion1 decoder went out of bounds\n"); \
return; \
} \
index = s->index_stream[index_stream_index++] * 4; \
}
#define INC_INDEX \
do { \
if (index >= 1023) { \
av_log(s->avctx, AV_LOG_ERROR, "Invalid index value.\n"); \
return; \
} \
index++; \
} while (0)
#define APPLY_C_PREDICTOR() \
predictor_pair = s->c_predictor_table[index]; \
horiz_pred += (predictor_pair >> 1); \
if (predictor_pair & 1) { \
GET_NEXT_INDEX() \
if (!index) { \
GET_NEXT_INDEX() \
predictor_pair = s->c_predictor_table[index]; \
horiz_pred += ((predictor_pair >> 1) * 5); \
if (predictor_pair & 1) \
GET_NEXT_INDEX() \
else \
INC_INDEX; \
} \
} else \
INC_INDEX;
#define APPLY_C_PREDICTOR_24() \
predictor_pair = s->c_predictor_table[index]; \
horiz_pred += (predictor_pair >> 1); \
if (predictor_pair & 1) { \
GET_NEXT_INDEX() \
if (!index) { \
GET_NEXT_INDEX() \
predictor_pair = s->fat_c_predictor_table[index]; \
horiz_pred += (predictor_pair >> 1); \
if (predictor_pair & 1) \
GET_NEXT_INDEX() \
else \
INC_INDEX; \
} \
} else \
INC_INDEX;
#define APPLY_Y_PREDICTOR() \
predictor_pair = s->y_predictor_table[index]; \
horiz_pred += (predictor_pair >> 1); \
if (predictor_pair & 1) { \
GET_NEXT_INDEX() \
if (!index) { \
GET_NEXT_INDEX() \
predictor_pair = s->y_predictor_table[index]; \
horiz_pred += ((predictor_pair >> 1) * 5); \
if (predictor_pair & 1) \
GET_NEXT_INDEX() \
else \
INC_INDEX; \
} \
} else \
INC_INDEX;
#define APPLY_Y_PREDICTOR_24() \
predictor_pair = s->y_predictor_table[index]; \
horiz_pred += (predictor_pair >> 1); \
if (predictor_pair & 1) { \
GET_NEXT_INDEX() \
if (!index) { \
GET_NEXT_INDEX() \
predictor_pair = s->fat_y_predictor_table[index]; \
horiz_pred += (predictor_pair >> 1); \
if (predictor_pair & 1) \
GET_NEXT_INDEX() \
else \
INC_INDEX; \
} \
} else \
INC_INDEX;
#define OUTPUT_PIXEL_PAIR() \
*current_pixel_pair = *vert_pred + horiz_pred; \
*vert_pred++ = *current_pixel_pair++;
static void truemotion1_decode_16bit(TrueMotion1Context *s)
{
int y;
int pixels_left; /* remaining pixels on this line */
unsigned int predictor_pair;
unsigned int horiz_pred;
unsigned int *vert_pred;
unsigned int *current_pixel_pair;
unsigned char *current_line = s->frame->data[0];
int keyframe = s->flags & FLAG_KEYFRAME;
/* these variables are for managing the stream of macroblock change bits */
const unsigned char *mb_change_bits = s->mb_change_bits;
unsigned char mb_change_byte;
unsigned char mb_change_byte_mask;
int mb_change_index;
/* these variables are for managing the main index stream */
int index_stream_index = 0; /* yes, the index into the index stream */
int index;
/* clean out the line buffer */
memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
GET_NEXT_INDEX();
for (y = 0; y < s->avctx->height; y++) {
/* re-init variables for the next line iteration */
horiz_pred = 0;
current_pixel_pair = (unsigned int *)current_line;
vert_pred = s->vert_pred;
mb_change_index = 0;
mb_change_byte = mb_change_bits[mb_change_index++];
mb_change_byte_mask = 0x01;
pixels_left = s->avctx->width;
while (pixels_left > 0) {
if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
switch (y & 3) {
case 0:
/* if macroblock width is 2, apply C-Y-C-Y; else
* apply C-Y-Y */
if (s->block_width == 2) {
APPLY_C_PREDICTOR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
APPLY_C_PREDICTOR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
} else {
APPLY_C_PREDICTOR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
}
break;
case 1:
case 3:
/* always apply 2 Y predictors on these iterations */
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
break;
case 2:
/* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
* depending on the macroblock type */
if (s->block_type == BLOCK_2x2) {
APPLY_C_PREDICTOR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
APPLY_C_PREDICTOR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
} else if (s->block_type == BLOCK_4x2) {
APPLY_C_PREDICTOR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
} else {
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR();
OUTPUT_PIXEL_PAIR();
}
break;
}
} else {
/* skip (copy) four pixels, but reassign the horizontal
* predictor */
*vert_pred++ = *current_pixel_pair++;
horiz_pred = *current_pixel_pair - *vert_pred;
*vert_pred++ = *current_pixel_pair++;
}
if (!keyframe) {
mb_change_byte_mask <<= 1;
/* next byte */
if (!mb_change_byte_mask) {
mb_change_byte = mb_change_bits[mb_change_index++];
mb_change_byte_mask = 0x01;
}
}
pixels_left -= 4;
}
/* next change row */
if (((y + 1) & 3) == 0)
mb_change_bits += s->mb_change_bits_row_size;
current_line += s->frame->linesize[0];
}
}
static void truemotion1_decode_24bit(TrueMotion1Context *s)
{
int y;
int pixels_left; /* remaining pixels on this line */
unsigned int predictor_pair;
unsigned int horiz_pred;
unsigned int *vert_pred;
unsigned int *current_pixel_pair;
unsigned char *current_line = s->frame->data[0];
int keyframe = s->flags & FLAG_KEYFRAME;
/* these variables are for managing the stream of macroblock change bits */
const unsigned char *mb_change_bits = s->mb_change_bits;
unsigned char mb_change_byte;
unsigned char mb_change_byte_mask;
int mb_change_index;
/* these variables are for managing the main index stream */
int index_stream_index = 0; /* yes, the index into the index stream */
int index;
/* clean out the line buffer */
memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
GET_NEXT_INDEX();
for (y = 0; y < s->avctx->height; y++) {
/* re-init variables for the next line iteration */
horiz_pred = 0;
current_pixel_pair = (unsigned int *)current_line;
vert_pred = s->vert_pred;
mb_change_index = 0;
mb_change_byte = mb_change_bits[mb_change_index++];
mb_change_byte_mask = 0x01;
pixels_left = s->avctx->width;
while (pixels_left > 0) {
if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
switch (y & 3) {
case 0:
/* if macroblock width is 2, apply C-Y-C-Y; else
* apply C-Y-Y */
if (s->block_width == 2) {
APPLY_C_PREDICTOR_24();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
APPLY_C_PREDICTOR_24();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
} else {
APPLY_C_PREDICTOR_24();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
}
break;
case 1:
case 3:
/* always apply 2 Y predictors on these iterations */
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
break;
case 2:
/* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
* depending on the macroblock type */
if (s->block_type == BLOCK_2x2) {
APPLY_C_PREDICTOR_24();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
APPLY_C_PREDICTOR_24();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
} else if (s->block_type == BLOCK_4x2) {
APPLY_C_PREDICTOR_24();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
} else {
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
APPLY_Y_PREDICTOR_24();
OUTPUT_PIXEL_PAIR();
}
break;
}
} else {
/* skip (copy) four pixels, but reassign the horizontal
* predictor */
*vert_pred++ = *current_pixel_pair++;
horiz_pred = *current_pixel_pair - *vert_pred;
*vert_pred++ = *current_pixel_pair++;
}
if (!keyframe) {
mb_change_byte_mask <<= 1;
/* next byte */
if (!mb_change_byte_mask) {
mb_change_byte = mb_change_bits[mb_change_index++];
mb_change_byte_mask = 0x01;
}
}
pixels_left -= 2;
}
/* next change row */
if (((y + 1) & 3) == 0)
mb_change_bits += s->mb_change_bits_row_size;
current_line += s->frame->linesize[0];
}
}
static int truemotion1_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int ret, buf_size = avpkt->size;
TrueMotion1Context *s = avctx->priv_data;
s->buf = buf;
s->size = buf_size;
if ((ret = truemotion1_decode_header(s)) < 0)
return ret;
if ((ret = ff_reget_buffer(avctx, s->frame)) < 0) {
av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return ret;
}
if (compression_types[s->compression].algorithm == ALGO_RGB24H) {
truemotion1_decode_24bit(s);
} else if (compression_types[s->compression].algorithm != ALGO_NOP) {
truemotion1_decode_16bit(s);
}
if ((ret = av_frame_ref(data, s->frame)) < 0)
return ret;
*got_frame = 1;
/* report that the buffer was completely consumed */
return buf_size;
}
static av_cold int truemotion1_decode_end(AVCodecContext *avctx)
{
TrueMotion1Context *s = avctx->priv_data;
av_frame_free(&s->frame);
av_free(s->vert_pred);
return 0;
}
AVCodec ff_truemotion1_decoder = {
.name = "truemotion1",
.long_name = NULL_IF_CONFIG_SMALL("Duck TrueMotion 1.0"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_TRUEMOTION1,
.priv_data_size = sizeof(TrueMotion1Context),
.init = truemotion1_decode_init,
.close = truemotion1_decode_end,
.decode = truemotion1_decode_frame,
.capabilities = CODEC_CAP_DR1,
};
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