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/*
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 * Cinepak Video Decoder
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 * Copyright (C) 2003 the ffmpeg project
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 *
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 */
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/**
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 * @file cinepak.c
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 * Cinepak video decoder
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 * by Ewald Snel <ewald@rambo.its.tudelft.nl>
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 * For more information on the Cinepak algorithm, visit:
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 *   http://www.csse.monash.edu.au/~timf/
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 */
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include "common.h"
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#include "avcodec.h"
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#include "dsputil.h"
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#define PALETTE_COUNT 256
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#define BE_16(x)  ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
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#define BE_32(x)  ((((uint8_t*)(x))[0] << 24) | \
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                   (((uint8_t*)(x))[1] << 16) | \
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                   (((uint8_t*)(x))[2] << 8) | \
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                    ((uint8_t*)(x))[3])
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typedef struct {
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    uint8_t  y0, y1, y2, y3;
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    uint8_t  u, v;
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} cvid_codebook_t;
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#define MAX_STRIPS      32
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typedef struct {
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    uint16_t          id;
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    uint16_t          x1, y1;
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    uint16_t          x2, y2;
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    cvid_codebook_t   v4_codebook[256];
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    cvid_codebook_t   v1_codebook[256];
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} cvid_strip_t;
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typedef struct CinepakContext {
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    AVCodecContext *avctx;
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    DSPContext dsp;
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    AVFrame frame;
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    AVFrame prev_frame;
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    unsigned char *data;
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    int size;
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    int width, height;
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    unsigned char palette[PALETTE_COUNT * 4];
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    int palette_video;
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    cvid_strip_t strips[MAX_STRIPS];
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} CinepakContext;
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static void cinepak_decode_codebook (cvid_codebook_t *codebook,
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                                     int chunk_id, int size, uint8_t *data)
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{
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    uint8_t *eod = (data + size);
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    uint32_t flag, mask;
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    int      i, n;
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    /* check if this chunk contains 4- or 6-element vectors */
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    n    = (chunk_id & 0x0400) ? 4 : 6;
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    flag = 0;
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    mask = 0;
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    for (i=0; i < 256; i++) {
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        if ((chunk_id & 0x0100) && !(mask >>= 1)) {
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            if ((data + 4) > eod)
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                break;
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            flag  = BE_32 (data);
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            data += 4;
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            mask  = 0x80000000;
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        }
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        if (!(chunk_id & 0x0100) || (flag & mask)) {
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            if ((data + n) > eod)
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                break;
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            if (n == 6) {
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                codebook[i].y0 = *data++;
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                codebook[i].y1 = *data++;
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                codebook[i].y2 = *data++;
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                codebook[i].y3 = *data++;
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                codebook[i].u  = 128 + *data++;
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                codebook[i].v  = 128 + *data++;
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            } else {
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                /* this codebook type indicates either greyscale or 
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                 * palettized video; if palettized, U & V components will
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                 * not be used so it is safe to set them to 128 for the
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                 * benefit of greyscale rendering in YUV420P */
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                codebook[i].y0 = *data++;
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                codebook[i].y1 = *data++;
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                codebook[i].y2 = *data++;
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                codebook[i].y3 = *data++;
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                codebook[i].u  = 128;
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                codebook[i].v  = 128;
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            }
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        }
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    }
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}
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static int cinepak_decode_vectors (CinepakContext *s, cvid_strip_t *strip,
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                                   int chunk_id, int size, uint8_t *data)
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{
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    uint8_t         *eod = (data + size);
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    uint32_t         flag, mask;
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    cvid_codebook_t *codebook;
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    unsigned int     i, j, x, y;
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    uint32_t         iy[4];
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    uint32_t         iu[2];
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    uint32_t         iv[2];
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    flag = 0;
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    mask = 0;
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    for (y=strip->y1; y < strip->y2; y+=4) {
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        iy[0] = strip->x1 + (y * s->frame.linesize[0]);
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        iy[1] = iy[0] + s->frame.linesize[0];
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        iy[2] = iy[1] + s->frame.linesize[0];
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        iy[3] = iy[2] + s->frame.linesize[0];
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        iu[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[1]);
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        iu[1] = iu[0] + s->frame.linesize[1];
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        iv[0] = (strip->x1/2) + ((y/2) * s->frame.linesize[2]);
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        iv[1] = iv[0] + s->frame.linesize[2];
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        for (x=strip->x1; x < strip->x2; x+=4) {
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            if ((chunk_id & 0x0100) && !(mask >>= 1)) {
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                if ((data + 4) > eod)
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                    return -1;
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                flag  = BE_32 (data);
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                data += 4;
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                mask  = 0x80000000;
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            }
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            if (!(chunk_id & 0x0100) || (flag & mask)) {
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                if (!(chunk_id & 0x0200) && !(mask >>= 1)) {
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                    if ((data + 4) > eod)
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                        return -1;
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                    flag  = BE_32 (data);
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                    data += 4;
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                    mask  = 0x80000000;
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                }
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                if ((chunk_id & 0x0200) || (~flag & mask)) {
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                    if (data >= eod)
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                        return -1;
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                    codebook = &strip->v1_codebook[*data++];
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                    s->frame.data[0][iy[0] + 0] = codebook->y0;
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                    s->frame.data[0][iy[0] + 1] = codebook->y0;
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                    s->frame.data[0][iy[1] + 0] = codebook->y0;
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                    s->frame.data[0][iy[1] + 1] = codebook->y0;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[0]] = codebook->u;
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                        s->frame.data[2][iv[0]] = codebook->v;
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                    }
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                    s->frame.data[0][iy[0] + 2] = codebook->y0;
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                    s->frame.data[0][iy[0] + 3] = codebook->y0;
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                    s->frame.data[0][iy[1] + 2] = codebook->y0;
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                    s->frame.data[0][iy[1] + 3] = codebook->y0;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[0] + 1] = codebook->u;
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                        s->frame.data[2][iv[0] + 1] = codebook->v;
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                    }
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                    s->frame.data[0][iy[2] + 0] = codebook->y0;
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                    s->frame.data[0][iy[2] + 1] = codebook->y0;
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                    s->frame.data[0][iy[3] + 0] = codebook->y0;
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                    s->frame.data[0][iy[3] + 1] = codebook->y0;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[1]] = codebook->u;
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                        s->frame.data[2][iv[1]] = codebook->v;
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                    }
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                    s->frame.data[0][iy[2] + 2] = codebook->y0;
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                    s->frame.data[0][iy[2] + 3] = codebook->y0;
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                    s->frame.data[0][iy[3] + 2] = codebook->y0;
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                    s->frame.data[0][iy[3] + 3] = codebook->y0;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[1] + 1] = codebook->u;
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                        s->frame.data[2][iv[1] + 1] = codebook->v;
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                    }
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                } else if (flag & mask) {
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                    if ((data + 4) > eod)
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                        return -1;
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                    codebook = &strip->v4_codebook[*data++];
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                    s->frame.data[0][iy[0] + 0] = codebook->y0;
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                    s->frame.data[0][iy[0] + 1] = codebook->y1;
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                    s->frame.data[0][iy[1] + 0] = codebook->y2;
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                    s->frame.data[0][iy[1] + 1] = codebook->y3;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[0]] = codebook->u;
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                        s->frame.data[2][iv[0]] = codebook->v;
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                    }
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                    codebook = &strip->v4_codebook[*data++];
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                    s->frame.data[0][iy[0] + 2] = codebook->y0;
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                    s->frame.data[0][iy[0] + 3] = codebook->y1;
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                    s->frame.data[0][iy[1] + 2] = codebook->y2;
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                    s->frame.data[0][iy[1] + 3] = codebook->y3;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[0] + 1] = codebook->u;
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                        s->frame.data[2][iv[0] + 1] = codebook->v;
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                    }
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                    codebook = &strip->v4_codebook[*data++];
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                    s->frame.data[0][iy[2] + 0] = codebook->y0;
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                    s->frame.data[0][iy[2] + 1] = codebook->y1;
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                    s->frame.data[0][iy[3] + 0] = codebook->y2;
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                    s->frame.data[0][iy[3] + 1] = codebook->y3;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[1]] = codebook->u;
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                        s->frame.data[2][iv[1]] = codebook->v;
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                    }
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                    codebook = &strip->v4_codebook[*data++];
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                    s->frame.data[0][iy[2] + 2] = codebook->y0;
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                    s->frame.data[0][iy[2] + 3] = codebook->y1;
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                    s->frame.data[0][iy[3] + 2] = codebook->y2;
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                    s->frame.data[0][iy[3] + 3] = codebook->y3;
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                    if (!s->palette_video) {
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                        s->frame.data[1][iu[1] + 1] = codebook->u;
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                        s->frame.data[2][iv[1] + 1] = codebook->v;
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                    }
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                }
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            } else {
260
                /* copy from the previous frame */
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                for (i = 0; i < 4; i++) {
262
                    for (j = 0; j < 4; j++) {
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                        s->frame.data[0][iy[i] + j] =
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                            s->prev_frame.data[0][iy[i] + j];
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                    }
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                }
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                for (i = 0; i < 2; i++) {
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                    for (j = 0; j < 2; j++) {
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                        s->frame.data[1][iu[i] + j] =
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                            s->prev_frame.data[1][iu[i] + j];
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                        s->frame.data[2][iv[i] + j] =
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                            s->prev_frame.data[2][iv[i] + j];
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                    }
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                }
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            }
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            iy[0] += 4;  iy[1] += 4;
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            iy[2] += 4;  iy[3] += 4;
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            iu[0] += 2;  iu[1] += 2;
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            iv[0] += 2;  iv[1] += 2;
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        }
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    }
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    return 0;
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}
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static int cinepak_decode_strip (CinepakContext *s,
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                                 cvid_strip_t *strip, uint8_t *data, int size)
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{
290
    uint8_t *eod = (data + size);
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    int      chunk_id, chunk_size;
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293
    /* coordinate sanity checks */
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    if (strip->x1 >= s->width  || strip->x2 > s->width  ||
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        strip->y1 >= s->height || strip->y2 > s->height ||
296
        strip->x1 >= strip->x2 || strip->y1 >= strip->y2)
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        return -1;
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299
    while ((data + 4) <= eod) {
300
        chunk_id   = BE_16 (&data[0]);
301
        chunk_size = BE_16 (&data[2]) - 4;
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        data      += 4;
303
        chunk_size = ((data + chunk_size) > eod) ? (eod - data) : chunk_size;
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305
        switch (chunk_id) {
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307
        case 0x2000:
308
        case 0x2100:
309
        case 0x2400:
310
        case 0x2500:
311
            cinepak_decode_codebook (strip->v4_codebook, chunk_id, 
312
                chunk_size, data);
313
            break;
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315
        case 0x2200:
316
        case 0x2300:
317
        case 0x2600:
318
        case 0x2700:
319
            cinepak_decode_codebook (strip->v1_codebook, chunk_id, 
320
                chunk_size, data);
321
            break;
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323
        case 0x3000:
324
        case 0x3100:
325
        case 0x3200:
326
            return cinepak_decode_vectors (s, strip, chunk_id, 
327
                chunk_size, data);
328
        }
329

    
330
        data += chunk_size;
331
    }
332

    
333
    return -1;
334
}
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static int cinepak_decode (CinepakContext *s)
337
{
338
    uint8_t      *eod = (s->data + s->size);
339
    int           i, result, strip_size, frame_flags, num_strips;
340
    int           y0 = 0;
341

    
342
    if (s->size < 10)
343
        return -1;
344

    
345
    frame_flags = s->data[0];
346
    num_strips  = BE_16 (&s->data[8]);
347
    s->data    += 10;
348

    
349
    if (num_strips > MAX_STRIPS)
350
        num_strips = MAX_STRIPS;
351

    
352
    for (i=0; i < num_strips; i++) {
353
        if ((s->data + 12) > eod)
354
            return -1;
355

    
356
        s->strips[i].id = BE_16 (s->data);
357
        s->strips[i].y1 = y0;
358
        s->strips[i].x1 = 0;
359
        s->strips[i].y2 = y0 + BE_16 (&s->data[8]);
360
        s->strips[i].x2 = s->avctx->width;
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362
        strip_size = BE_16 (&s->data[2]) - 12;
363
        s->data   += 12;
364
        strip_size = ((s->data + strip_size) > eod) ? (eod - s->data) : strip_size;
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366
        if ((i > 0) && !(frame_flags & 0x01)) {
367
            memcpy (s->strips[i].v4_codebook, s->strips[i-1].v4_codebook,
368
                sizeof(s->strips[i].v4_codebook));
369
            memcpy (s->strips[i].v1_codebook, s->strips[i-1].v1_codebook,
370
                sizeof(s->strips[i].v1_codebook));
371
        }
372

    
373
        result = cinepak_decode_strip (s, &s->strips[i], s->data, strip_size);
374

    
375
        if (result != 0)
376
            return result;
377

    
378
        s->data += strip_size;
379
        y0    = s->strips[i].y2;
380
    }
381
    return 0;
382
}
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384
static int cinepak_decode_init(AVCodecContext *avctx)
385
{
386
    CinepakContext *s = (CinepakContext *)avctx->priv_data;
387
/*
388
    int i;
389
    unsigned char r, g, b;
390
    unsigned char *raw_palette;
391
    unsigned int *palette32;
392
*/
393

    
394
    s->avctx = avctx;
395
    s->width = (avctx->width + 3) & ~3;
396
    s->height = (avctx->height + 3) & ~3;
397

    
398
// check for paletted data
399
s->palette_video = 0;
400

    
401

    
402
    avctx->pix_fmt = PIX_FMT_YUV420P;
403
    avctx->has_b_frames = 0;
404
    dsputil_init(&s->dsp, avctx);
405

    
406
    s->frame.data[0] = s->prev_frame.data[0] = NULL;
407

    
408
    return 0;
409
}
410

    
411
static int cinepak_decode_frame(AVCodecContext *avctx,
412
                                void *data, int *data_size,
413
                                uint8_t *buf, int buf_size)
414
{
415
    CinepakContext *s = (CinepakContext *)avctx->priv_data;
416

    
417
    s->data = buf;
418
    s->size = buf_size;
419

    
420
    if (avctx->get_buffer(avctx, &s->frame)) {
421
        av_log(avctx, AV_LOG_ERROR, "  Cinepak: get_buffer() failed\n");
422
        return -1;
423
    }
424

    
425
    cinepak_decode(s);
426

    
427
    if (s->prev_frame.data[0])
428
        avctx->release_buffer(avctx, &s->prev_frame);
429

    
430
    /* shuffle frames */
431
    s->prev_frame = s->frame;
432

    
433
    *data_size = sizeof(AVFrame);
434
    *(AVFrame*)data = s->frame;
435

    
436
    /* report that the buffer was completely consumed */
437
    return buf_size;
438
}
439

    
440
static int cinepak_decode_end(AVCodecContext *avctx)
441
{
442
    CinepakContext *s = (CinepakContext *)avctx->priv_data;
443

    
444
    if (s->prev_frame.data[0])
445
        avctx->release_buffer(avctx, &s->prev_frame);
446

    
447
    return 0;
448
}
449

    
450
AVCodec cinepak_decoder = {
451
    "cinepak",
452
    CODEC_TYPE_VIDEO,
453
    CODEC_ID_CINEPAK,
454
    sizeof(CinepakContext),
455
    cinepak_decode_init,
456
    NULL,
457
    cinepak_decode_end,
458
    cinepak_decode_frame,
459
    CODEC_CAP_DR1,
460
};