668 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			668 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Sierra VMD Audio & Video Decoders
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 * Copyright (C) 2004 the ffmpeg project
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg 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 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Sierra VMD audio & video decoders
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 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
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 * for more information on the Sierra VMD format, visit:
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 *   http://www.pcisys.net/~melanson/codecs/
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 *
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 * The video decoder outputs PAL8 colorspace data. The decoder expects
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 * a 0x330-byte VMD file header to be transmitted via extradata during
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 * codec initialization. Each encoded frame that is sent to this decoder
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 * is expected to be prepended with the appropriate 16-byte frame
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 * information record from the VMD file.
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 *
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 * The audio decoder, like the video decoder, expects each encoded data
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 * chunk to be prepended with the appropriate 16-byte frame information
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 * record from the VMD file. It does not require the 0x330-byte VMD file
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 * header, but it does need the audio setup parameters passed in through
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 * normal libavcodec API means.
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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 "libavutil/common.h"
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#include "libavutil/intreadwrite.h"
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#include "avcodec.h"
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#define VMD_HEADER_SIZE 0x330
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#define PALETTE_COUNT 256
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/*
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 * Video Decoder
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 */
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typedef struct VmdVideoContext {
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    AVCodecContext *avctx;
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    AVFrame frame;
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    AVFrame prev_frame;
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    const unsigned char *buf;
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    int size;
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    unsigned char palette[PALETTE_COUNT * 4];
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    unsigned char *unpack_buffer;
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    int unpack_buffer_size;
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    int x_off, y_off;
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} VmdVideoContext;
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#define QUEUE_SIZE 0x1000
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#define QUEUE_MASK 0x0FFF
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static void lz_unpack(const unsigned char *src, int src_len,
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                      unsigned char *dest, int dest_len)
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{
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    const unsigned char *s;
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    const unsigned char *s_end;
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    unsigned char *d;
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    unsigned char *d_end;
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    unsigned char queue[QUEUE_SIZE];
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    unsigned int qpos;
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    unsigned int dataleft;
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    unsigned int chainofs;
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    unsigned int chainlen;
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    unsigned int speclen;
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    unsigned char tag;
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    unsigned int i, j;
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    s = src;
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    s_end = src + src_len;
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    d = dest;
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    d_end = d + dest_len;
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    if (s_end - s < 8)
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        return;
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    dataleft = AV_RL32(s);
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    s += 4;
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    memset(queue, 0x20, QUEUE_SIZE);
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    if (AV_RL32(s) == 0x56781234) {
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        s += 4;
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        qpos = 0x111;
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        speclen = 0xF + 3;
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    } else {
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        qpos = 0xFEE;
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        speclen = 100;  /* no speclen */
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    }
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    while (s_end - s > 0 && dataleft > 0) {
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        tag = *s++;
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        if ((tag == 0xFF) && (dataleft > 8)) {
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            if (d_end - d < 8 || s_end - s < 8)
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                return;
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            for (i = 0; i < 8; i++) {
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                queue[qpos++] = *d++ = *s++;
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                qpos &= QUEUE_MASK;
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            }
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            dataleft -= 8;
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        } else {
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            for (i = 0; i < 8; i++) {
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                if (dataleft == 0)
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                    break;
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                if (tag & 0x01) {
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                    if (d_end - d < 1 || s_end - s < 1)
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                        return;
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                    queue[qpos++] = *d++ = *s++;
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                    qpos &= QUEUE_MASK;
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                    dataleft--;
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                } else {
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                    if (s_end - s < 2)
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                        return;
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                    chainofs = *s++;
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                    chainofs |= ((*s & 0xF0) << 4);
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                    chainlen = (*s++ & 0x0F) + 3;
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                    if (chainlen == speclen) {
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                        if (s_end - s < 1)
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                            return;
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                        chainlen = *s++ + 0xF + 3;
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                    }
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                    if (d_end - d < chainlen)
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                        return;
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                    for (j = 0; j < chainlen; j++) {
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                        *d = queue[chainofs++ & QUEUE_MASK];
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                        queue[qpos++] = *d++;
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                        qpos &= QUEUE_MASK;
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                    }
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                    dataleft -= chainlen;
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                }
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                tag >>= 1;
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            }
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        }
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    }
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}
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static int rle_unpack(const unsigned char *src, int src_len, int src_count,
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                      unsigned char *dest, int dest_len)
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{
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    const unsigned char *ps;
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    const unsigned char *ps_end;
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    unsigned char *pd;
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    int i, l;
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    unsigned char *dest_end = dest + dest_len;
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    ps = src;
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    ps_end = src + src_len;
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    pd = dest;
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    if (src_count & 1) {
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        if (ps_end - ps < 1)
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            return 0;
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        *pd++ = *ps++;
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    }
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    src_count >>= 1;
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    i = 0;
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    do {
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        if (ps_end - ps < 1)
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            break;
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        l = *ps++;
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        if (l & 0x80) {
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            l = (l & 0x7F) * 2;
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            if (dest_end - pd < l || ps_end - ps < l)
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                return ps - src;
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            memcpy(pd, ps, l);
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            ps += l;
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            pd += l;
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        } else {
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            if (dest_end - pd < i || ps_end - ps < 2)
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                return ps - src;
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            for (i = 0; i < l; i++) {
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                *pd++ = ps[0];
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                *pd++ = ps[1];
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            }
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            ps += 2;
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        }
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        i += l;
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    } while (i < src_count);
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    return ps - src;
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}
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static void vmd_decode(VmdVideoContext *s)
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{
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    int i;
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    unsigned int *palette32;
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    unsigned char r, g, b;
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    /* point to the start of the encoded data */
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    const unsigned char *p = s->buf + 16;
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    const unsigned char *p_end = s->buf + s->size;
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    const unsigned char *pb;
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    const unsigned char *pb_end;
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    unsigned char meth;
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    unsigned char *dp;   /* pointer to current frame */
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    unsigned char *pp;   /* pointer to previous frame */
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    unsigned char len;
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    int ofs;
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    int frame_x, frame_y;
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    int frame_width, frame_height;
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    frame_x = AV_RL16(&s->buf[6]);
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    frame_y = AV_RL16(&s->buf[8]);
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    frame_width = AV_RL16(&s->buf[10]) - frame_x + 1;
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    frame_height = AV_RL16(&s->buf[12]) - frame_y + 1;
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    if (frame_x < 0 || frame_width < 0 ||
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        frame_x >= s->avctx->width ||
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        frame_width > s->avctx->width ||
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        frame_x + frame_width > s->avctx->width)
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        return;
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    if (frame_y < 0 || frame_height < 0 ||
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        frame_y >= s->avctx->height ||
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        frame_height > s->avctx->height ||
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        frame_y + frame_height > s->avctx->height)
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        return;
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    if ((frame_width == s->avctx->width && frame_height == s->avctx->height) &&
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        (frame_x || frame_y)) {
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        s->x_off = frame_x;
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        s->y_off = frame_y;
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    }
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    frame_x -= s->x_off;
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    frame_y -= s->y_off;
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    /* if only a certain region will be updated, copy the entire previous
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     * frame before the decode */
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    if (s->prev_frame.data[0] &&
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        (frame_x || frame_y || (frame_width != s->avctx->width) ||
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        (frame_height != s->avctx->height))) {
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        memcpy(s->frame.data[0], s->prev_frame.data[0],
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            s->avctx->height * s->frame.linesize[0]);
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    }
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    /* check if there is a new palette */
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    if (s->buf[15] & 0x02) {
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        if (p_end - p < 2 + 3 * PALETTE_COUNT)
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            return;
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        p += 2;
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        palette32 = (unsigned int *)s->palette;
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        for (i = 0; i < PALETTE_COUNT; i++) {
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            r = *p++ * 4;
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            g = *p++ * 4;
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            b = *p++ * 4;
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            palette32[i] = 0xFFU << 24 | r << 16 | g << 8 | b;
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            palette32[i] |= palette32[i] >> 6 & 0x30303;
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        }
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    }
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    if (p < p_end) {
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        /* originally UnpackFrame in VAG's code */
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        pb = p;
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        pb_end = p_end;
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        meth = *pb++;
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        if (meth & 0x80) {
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            lz_unpack(pb, p_end - pb, s->unpack_buffer, s->unpack_buffer_size);
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            meth &= 0x7F;
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            pb = s->unpack_buffer;
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            pb_end = s->unpack_buffer + s->unpack_buffer_size;
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        }
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        dp = &s->frame.data[0][frame_y * s->frame.linesize[0] + frame_x];
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        pp = &s->prev_frame.data[0][frame_y * s->prev_frame.linesize[0] + frame_x];
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        switch (meth) {
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        case 1:
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            for (i = 0; i < frame_height; i++) {
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                ofs = 0;
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                do {
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                    if (pb_end - pb < 1)
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                        return;
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                    len = *pb++;
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                    if (len & 0x80) {
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                        len = (len & 0x7F) + 1;
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                        if (ofs + len > frame_width || pb_end - pb < len)
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                            return;
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                        memcpy(&dp[ofs], pb, len);
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                        pb += len;
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                        ofs += len;
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                    } else {
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                        /* interframe pixel copy */
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                        if (ofs + len + 1 > frame_width || !s->prev_frame.data[0])
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                            return;
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                        memcpy(&dp[ofs], &pp[ofs], len + 1);
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                        ofs += len + 1;
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                    }
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                } while (ofs < frame_width);
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                if (ofs > frame_width) {
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                    av_log(s->avctx, AV_LOG_ERROR, "offset > width (%d > %d)\n",
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                        ofs, frame_width);
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                    break;
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                }
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                dp += s->frame.linesize[0];
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                pp += s->prev_frame.linesize[0];
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            }
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            break;
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        case 2:
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            for (i = 0; i < frame_height; i++) {
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                if (pb_end -pb < frame_width)
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                    return;
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                memcpy(dp, pb, frame_width);
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                pb += frame_width;
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                dp += s->frame.linesize[0];
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                pp += s->prev_frame.linesize[0];
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            }
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            break;
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        case 3:
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            for (i = 0; i < frame_height; i++) {
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                ofs = 0;
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                do {
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                    if (pb_end - pb < 1)
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                        return;
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                    len = *pb++;
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                    if (len & 0x80) {
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                        len = (len & 0x7F) + 1;
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                        if (pb_end - pb < 1)
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                            return;
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                        if (*pb++ == 0xFF)
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                            len = rle_unpack(pb, pb_end - pb, len, &dp[ofs], frame_width - ofs);
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                        else {
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                        if (pb_end - pb < len)
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                            return;
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                            memcpy(&dp[ofs], pb, len);
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                        }
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                        pb += len;
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                        ofs += len;
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                    } else {
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                        /* interframe pixel copy */
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                        if (ofs + len + 1 > frame_width || !s->prev_frame.data[0])
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                            return;
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                        memcpy(&dp[ofs], &pp[ofs], len + 1);
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                        ofs += len + 1;
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                    }
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                } while (ofs < frame_width);
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                if (ofs > frame_width) {
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                    av_log(s->avctx, AV_LOG_ERROR, "offset > width (%d > %d)\n",
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                        ofs, frame_width);
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                }
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                dp += s->frame.linesize[0];
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                pp += s->prev_frame.linesize[0];
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            }
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            break;
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        }
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    }
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}
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static av_cold int vmdvideo_decode_init(AVCodecContext *avctx)
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{
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    VmdVideoContext *s = avctx->priv_data;
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    int i;
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    unsigned int *palette32;
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    int palette_index = 0;
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    unsigned char r, g, b;
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    unsigned char *vmd_header;
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    unsigned char *raw_palette;
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    s->avctx = avctx;
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    avctx->pix_fmt = AV_PIX_FMT_PAL8;
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    /* make sure the VMD header made it */
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    if (s->avctx->extradata_size != VMD_HEADER_SIZE) {
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        av_log(s->avctx, AV_LOG_ERROR, "expected extradata size of %d\n",
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            VMD_HEADER_SIZE);
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        return -1;
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    }
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    vmd_header = (unsigned char *)avctx->extradata;
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    s->unpack_buffer_size = AV_RL32(&vmd_header[800]);
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    s->unpack_buffer = av_malloc(s->unpack_buffer_size);
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    if (!s->unpack_buffer)
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        return -1;
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    /* load up the initial palette */
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    raw_palette = &vmd_header[28];
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    palette32 = (unsigned int *)s->palette;
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    for (i = 0; i < PALETTE_COUNT; i++) {
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        r = raw_palette[palette_index++] * 4;
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        g = raw_palette[palette_index++] * 4;
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        b = raw_palette[palette_index++] * 4;
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        palette32[i] = (r << 16) | (g << 8) | (b);
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    }
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    avcodec_get_frame_defaults(&s->frame);
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    avcodec_get_frame_defaults(&s->prev_frame);
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    return 0;
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}
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static int vmdvideo_decode_frame(AVCodecContext *avctx,
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                                 void *data, int *data_size,
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                                 AVPacket *avpkt)
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{
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    const uint8_t *buf = avpkt->data;
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    int buf_size = avpkt->size;
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    VmdVideoContext *s = avctx->priv_data;
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    s->buf = buf;
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    s->size = buf_size;
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    if (buf_size < 16)
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        return buf_size;
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    s->frame.reference = 3;
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    if (avctx->get_buffer(avctx, &s->frame)) {
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        av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
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        return -1;
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    }
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    vmd_decode(s);
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    /* make the palette available on the way out */
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    memcpy(s->frame.data[1], s->palette, PALETTE_COUNT * 4);
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    /* shuffle frames */
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    FFSWAP(AVFrame, s->frame, s->prev_frame);
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    if (s->frame.data[0])
 | 
						|
        avctx->release_buffer(avctx, &s->frame);
 | 
						|
 | 
						|
    *data_size = sizeof(AVFrame);
 | 
						|
    *(AVFrame*)data = s->prev_frame;
 | 
						|
 | 
						|
    /* report that the buffer was completely consumed */
 | 
						|
    return buf_size;
 | 
						|
}
 | 
						|
 | 
						|
static av_cold int vmdvideo_decode_end(AVCodecContext *avctx)
 | 
						|
{
 | 
						|
    VmdVideoContext *s = avctx->priv_data;
 | 
						|
 | 
						|
    if (s->prev_frame.data[0])
 | 
						|
        avctx->release_buffer(avctx, &s->prev_frame);
 | 
						|
    av_free(s->unpack_buffer);
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
 * Audio Decoder
 | 
						|
 */
 | 
						|
 | 
						|
#define BLOCK_TYPE_AUDIO    1
 | 
						|
#define BLOCK_TYPE_INITIAL  2
 | 
						|
#define BLOCK_TYPE_SILENCE  3
 | 
						|
 | 
						|
typedef struct VmdAudioContext {
 | 
						|
    AVFrame frame;
 | 
						|
    int out_bps;
 | 
						|
    int chunk_size;
 | 
						|
} VmdAudioContext;
 | 
						|
 | 
						|
static const uint16_t vmdaudio_table[128] = {
 | 
						|
    0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
 | 
						|
    0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
 | 
						|
    0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
 | 
						|
    0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
 | 
						|
    0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
 | 
						|
    0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
 | 
						|
    0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
 | 
						|
    0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
 | 
						|
    0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
 | 
						|
    0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
 | 
						|
    0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
 | 
						|
    0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
 | 
						|
    0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
 | 
						|
};
 | 
						|
 | 
						|
static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
 | 
						|
{
 | 
						|
    VmdAudioContext *s = avctx->priv_data;
 | 
						|
 | 
						|
    if (avctx->channels < 1 || avctx->channels > 2) {
 | 
						|
        av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
 | 
						|
        return AVERROR(EINVAL);
 | 
						|
    }
 | 
						|
    if (avctx->block_align < 1) {
 | 
						|
        av_log(avctx, AV_LOG_ERROR, "invalid block align\n");
 | 
						|
        return AVERROR(EINVAL);
 | 
						|
    }
 | 
						|
 | 
						|
    if (avctx->bits_per_coded_sample == 16)
 | 
						|
        avctx->sample_fmt = AV_SAMPLE_FMT_S16;
 | 
						|
    else
 | 
						|
        avctx->sample_fmt = AV_SAMPLE_FMT_U8;
 | 
						|
    s->out_bps = av_get_bytes_per_sample(avctx->sample_fmt);
 | 
						|
 | 
						|
    s->chunk_size = avctx->block_align + avctx->channels * (s->out_bps == 2);
 | 
						|
 | 
						|
    avcodec_get_frame_defaults(&s->frame);
 | 
						|
    avctx->coded_frame = &s->frame;
 | 
						|
 | 
						|
    av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
 | 
						|
           "block align = %d, sample rate = %d\n",
 | 
						|
           avctx->channels, avctx->bits_per_coded_sample, avctx->block_align,
 | 
						|
           avctx->sample_rate);
 | 
						|
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
static void decode_audio_s16(int16_t *out, const uint8_t *buf, int buf_size,
 | 
						|
                             int channels)
 | 
						|
{
 | 
						|
    int ch;
 | 
						|
    const uint8_t *buf_end = buf + buf_size;
 | 
						|
    int predictor[2];
 | 
						|
    int st = channels - 1;
 | 
						|
 | 
						|
    /* decode initial raw sample */
 | 
						|
    for (ch = 0; ch < channels; ch++) {
 | 
						|
        predictor[ch] = (int16_t)AV_RL16(buf);
 | 
						|
        buf += 2;
 | 
						|
        *out++ = predictor[ch];
 | 
						|
    }
 | 
						|
 | 
						|
    /* decode DPCM samples */
 | 
						|
    ch = 0;
 | 
						|
    while (buf < buf_end) {
 | 
						|
        uint8_t b = *buf++;
 | 
						|
        if (b & 0x80)
 | 
						|
            predictor[ch] -= vmdaudio_table[b & 0x7F];
 | 
						|
        else
 | 
						|
            predictor[ch] += vmdaudio_table[b];
 | 
						|
        predictor[ch] = av_clip_int16(predictor[ch]);
 | 
						|
        *out++ = predictor[ch];
 | 
						|
        ch ^= st;
 | 
						|
    }
 | 
						|
}
 | 
						|
 | 
						|
static int vmdaudio_decode_frame(AVCodecContext *avctx, void *data,
 | 
						|
                                 int *got_frame_ptr, AVPacket *avpkt)
 | 
						|
{
 | 
						|
    const uint8_t *buf = avpkt->data;
 | 
						|
    const uint8_t *buf_end;
 | 
						|
    int buf_size = avpkt->size;
 | 
						|
    VmdAudioContext *s = avctx->priv_data;
 | 
						|
    int block_type, silent_chunks, audio_chunks;
 | 
						|
    int ret;
 | 
						|
    uint8_t *output_samples_u8;
 | 
						|
    int16_t *output_samples_s16;
 | 
						|
 | 
						|
    if (buf_size < 16) {
 | 
						|
        av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
 | 
						|
        *got_frame_ptr = 0;
 | 
						|
        return buf_size;
 | 
						|
    }
 | 
						|
 | 
						|
    block_type = buf[6];
 | 
						|
    if (block_type < BLOCK_TYPE_AUDIO || block_type > BLOCK_TYPE_SILENCE) {
 | 
						|
        av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
 | 
						|
        return AVERROR(EINVAL);
 | 
						|
    }
 | 
						|
    buf      += 16;
 | 
						|
    buf_size -= 16;
 | 
						|
 | 
						|
    /* get number of silent chunks */
 | 
						|
    silent_chunks = 0;
 | 
						|
    if (block_type == BLOCK_TYPE_INITIAL) {
 | 
						|
        uint32_t flags;
 | 
						|
        if (buf_size < 4) {
 | 
						|
            av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
 | 
						|
            return AVERROR(EINVAL);
 | 
						|
        }
 | 
						|
        flags         = AV_RB32(buf);
 | 
						|
        silent_chunks = av_popcount(flags);
 | 
						|
        buf      += 4;
 | 
						|
        buf_size -= 4;
 | 
						|
    } else if (block_type == BLOCK_TYPE_SILENCE) {
 | 
						|
        silent_chunks = 1;
 | 
						|
        buf_size = 0; // should already be zero but set it just to be sure
 | 
						|
    }
 | 
						|
 | 
						|
    /* ensure output buffer is large enough */
 | 
						|
    audio_chunks = buf_size / s->chunk_size;
 | 
						|
 | 
						|
    /* get output buffer */
 | 
						|
    s->frame.nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) / avctx->channels;
 | 
						|
    if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
 | 
						|
        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 | 
						|
        return ret;
 | 
						|
    }
 | 
						|
    output_samples_u8  = s->frame.data[0];
 | 
						|
    output_samples_s16 = (int16_t *)s->frame.data[0];
 | 
						|
 | 
						|
    /* decode silent chunks */
 | 
						|
    if (silent_chunks > 0) {
 | 
						|
        int silent_size = avctx->block_align * silent_chunks;
 | 
						|
        if (s->out_bps == 2) {
 | 
						|
            memset(output_samples_s16, 0x00, silent_size * 2);
 | 
						|
            output_samples_s16 += silent_size;
 | 
						|
        } else {
 | 
						|
            memset(output_samples_u8,  0x80, silent_size);
 | 
						|
            output_samples_u8 += silent_size;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    /* decode audio chunks */
 | 
						|
    if (audio_chunks > 0) {
 | 
						|
        buf_end = buf + buf_size;
 | 
						|
        while ( buf_end - buf >= s->chunk_size) {
 | 
						|
            if (s->out_bps == 2) {
 | 
						|
                decode_audio_s16(output_samples_s16, buf, s->chunk_size,
 | 
						|
                                 avctx->channels);
 | 
						|
                output_samples_s16 += avctx->block_align;
 | 
						|
            } else {
 | 
						|
                memcpy(output_samples_u8, buf, s->chunk_size);
 | 
						|
                output_samples_u8  += avctx->block_align;
 | 
						|
            }
 | 
						|
            buf += s->chunk_size;
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    *got_frame_ptr   = 1;
 | 
						|
    *(AVFrame *)data = s->frame;
 | 
						|
 | 
						|
    return avpkt->size;
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
/*
 | 
						|
 * Public Data Structures
 | 
						|
 */
 | 
						|
 | 
						|
AVCodec ff_vmdvideo_decoder = {
 | 
						|
    .name           = "vmdvideo",
 | 
						|
    .type           = AVMEDIA_TYPE_VIDEO,
 | 
						|
    .id             = AV_CODEC_ID_VMDVIDEO,
 | 
						|
    .priv_data_size = sizeof(VmdVideoContext),
 | 
						|
    .init           = vmdvideo_decode_init,
 | 
						|
    .close          = vmdvideo_decode_end,
 | 
						|
    .decode         = vmdvideo_decode_frame,
 | 
						|
    .capabilities   = CODEC_CAP_DR1,
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD video"),
 | 
						|
};
 | 
						|
 | 
						|
AVCodec ff_vmdaudio_decoder = {
 | 
						|
    .name           = "vmdaudio",
 | 
						|
    .type           = AVMEDIA_TYPE_AUDIO,
 | 
						|
    .id             = AV_CODEC_ID_VMDAUDIO,
 | 
						|
    .priv_data_size = sizeof(VmdAudioContext),
 | 
						|
    .init           = vmdaudio_decode_init,
 | 
						|
    .decode         = vmdaudio_decode_frame,
 | 
						|
    .capabilities   = CODEC_CAP_DR1,
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD audio"),
 | 
						|
};
 |