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Rev | Author | Line No. | Line |
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4349 | Serge | 1 | /* |
2 | * Wing Commander/Xan Video Decoder |
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3 | * Copyright (C) 2003 the ffmpeg project |
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4 | * |
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5 | * This file is part of FFmpeg. |
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6 | * |
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7 | * FFmpeg is free software; you can redistribute it and/or |
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8 | * modify it under the terms of the GNU Lesser General Public |
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9 | * License as published by the Free Software Foundation; either |
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10 | * version 2.1 of the License, or (at your option) any later version. |
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11 | * |
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12 | * FFmpeg is distributed in the hope that it will be useful, |
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13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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15 | * Lesser General Public License for more details. |
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16 | * |
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17 | * You should have received a copy of the GNU Lesser General Public |
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18 | * License along with FFmpeg; if not, write to the Free Software |
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19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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20 | */ |
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21 | |||
22 | /** |
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23 | * @file |
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24 | * Xan video decoder for Wing Commander III computer game |
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25 | * by Mario Brito (mbrito@student.dei.uc.pt) |
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26 | * and Mike Melanson (melanson@pcisys.net) |
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27 | * |
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28 | * The xan_wc3 decoder outputs PAL8 data. |
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29 | */ |
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30 | |||
31 | #include |
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32 | #include |
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33 | #include |
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34 | |||
35 | #include "libavutil/intreadwrite.h" |
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36 | #include "libavutil/mem.h" |
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37 | #include "avcodec.h" |
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38 | #include "bytestream.h" |
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39 | #define BITSTREAM_READER_LE |
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40 | #include "get_bits.h" |
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41 | #include "internal.h" |
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42 | |||
43 | #define RUNTIME_GAMMA 0 |
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44 | |||
45 | #define VGA__TAG MKTAG('V', 'G', 'A', ' ') |
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46 | #define PALT_TAG MKTAG('P', 'A', 'L', 'T') |
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47 | #define SHOT_TAG MKTAG('S', 'H', 'O', 'T') |
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48 | #define PALETTE_COUNT 256 |
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49 | #define PALETTE_SIZE (PALETTE_COUNT * 3) |
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50 | #define PALETTES_MAX 256 |
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51 | |||
52 | typedef struct XanContext { |
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53 | |||
54 | AVCodecContext *avctx; |
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55 | AVFrame *last_frame; |
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56 | |||
57 | const uint8_t *buf; |
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58 | int size; |
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59 | |||
60 | /* scratch space */ |
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61 | uint8_t *buffer1; |
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62 | int buffer1_size; |
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63 | uint8_t *buffer2; |
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64 | int buffer2_size; |
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65 | |||
66 | unsigned *palettes; |
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67 | int palettes_count; |
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68 | int cur_palette; |
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69 | |||
70 | int frame_size; |
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71 | |||
72 | } XanContext; |
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73 | |||
74 | static av_cold int xan_decode_end(AVCodecContext *avctx); |
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75 | |||
76 | static av_cold int xan_decode_init(AVCodecContext *avctx) |
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77 | { |
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78 | XanContext *s = avctx->priv_data; |
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79 | |||
80 | s->avctx = avctx; |
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81 | s->frame_size = 0; |
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82 | |||
83 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
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84 | |||
85 | s->buffer1_size = avctx->width * avctx->height; |
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86 | s->buffer1 = av_malloc(s->buffer1_size); |
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87 | if (!s->buffer1) |
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88 | return AVERROR(ENOMEM); |
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89 | s->buffer2_size = avctx->width * avctx->height; |
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90 | s->buffer2 = av_malloc(s->buffer2_size + 130); |
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91 | if (!s->buffer2) { |
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92 | av_freep(&s->buffer1); |
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93 | return AVERROR(ENOMEM); |
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94 | } |
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95 | s->last_frame = av_frame_alloc(); |
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96 | if (!s->last_frame) { |
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97 | xan_decode_end(avctx); |
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98 | return AVERROR(ENOMEM); |
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99 | } |
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100 | |||
101 | return 0; |
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102 | } |
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103 | |||
104 | static int xan_huffman_decode(uint8_t *dest, int dest_len, |
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105 | const uint8_t *src, int src_len) |
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106 | { |
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107 | uint8_t byte = *src++; |
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108 | uint8_t ival = byte + 0x16; |
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109 | const uint8_t * ptr = src + byte*2; |
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110 | int ptr_len = src_len - 1 - byte*2; |
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111 | uint8_t val = ival; |
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112 | uint8_t *dest_end = dest + dest_len; |
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113 | uint8_t *dest_start = dest; |
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114 | GetBitContext gb; |
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115 | |||
116 | if (ptr_len < 0) |
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117 | return AVERROR_INVALIDDATA; |
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118 | |||
119 | init_get_bits(&gb, ptr, ptr_len * 8); |
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120 | |||
121 | while (val != 0x16) { |
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122 | unsigned idx = val - 0x17 + get_bits1(&gb) * byte; |
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123 | if (idx >= 2 * byte) |
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124 | return AVERROR_INVALIDDATA; |
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125 | val = src[idx]; |
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126 | |||
127 | if (val < 0x16) { |
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128 | if (dest >= dest_end) |
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129 | return dest_len; |
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130 | *dest++ = val; |
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131 | val = ival; |
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132 | } |
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133 | } |
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134 | |||
135 | return dest - dest_start; |
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136 | } |
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137 | |||
138 | /** |
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139 | * unpack simple compression |
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140 | * |
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141 | * @param dest destination buffer of dest_len, must be padded with at least 130 bytes |
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142 | */ |
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143 | static void xan_unpack(uint8_t *dest, int dest_len, |
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144 | const uint8_t *src, int src_len) |
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145 | { |
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146 | uint8_t opcode; |
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147 | int size; |
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148 | uint8_t *dest_org = dest; |
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149 | uint8_t *dest_end = dest + dest_len; |
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150 | GetByteContext ctx; |
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151 | |||
152 | bytestream2_init(&ctx, src, src_len); |
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153 | while (dest < dest_end && bytestream2_get_bytes_left(&ctx)) { |
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154 | opcode = bytestream2_get_byte(&ctx); |
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155 | |||
156 | if (opcode < 0xe0) { |
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157 | int size2, back; |
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158 | if ((opcode & 0x80) == 0) { |
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159 | size = opcode & 3; |
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160 | |||
161 | back = ((opcode & 0x60) << 3) + bytestream2_get_byte(&ctx) + 1; |
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162 | size2 = ((opcode & 0x1c) >> 2) + 3; |
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163 | } else if ((opcode & 0x40) == 0) { |
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164 | size = bytestream2_peek_byte(&ctx) >> 6; |
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165 | |||
166 | back = (bytestream2_get_be16(&ctx) & 0x3fff) + 1; |
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167 | size2 = (opcode & 0x3f) + 4; |
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168 | } else { |
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169 | size = opcode & 3; |
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170 | |||
171 | back = ((opcode & 0x10) << 12) + bytestream2_get_be16(&ctx) + 1; |
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172 | size2 = ((opcode & 0x0c) << 6) + bytestream2_get_byte(&ctx) + 5; |
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173 | } |
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174 | |||
175 | if (dest_end - dest < size + size2 || |
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176 | dest + size - dest_org < back || |
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177 | bytestream2_get_bytes_left(&ctx) < size) |
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178 | return; |
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179 | bytestream2_get_buffer(&ctx, dest, size); |
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180 | dest += size; |
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181 | av_memcpy_backptr(dest, back, size2); |
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182 | dest += size2; |
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183 | } else { |
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184 | int finish = opcode >= 0xfc; |
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185 | size = finish ? opcode & 3 : ((opcode & 0x1f) << 2) + 4; |
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186 | |||
187 | if (dest_end - dest < size || bytestream2_get_bytes_left(&ctx) < size) |
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188 | return; |
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189 | bytestream2_get_buffer(&ctx, dest, size); |
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190 | dest += size; |
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191 | if (finish) |
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192 | return; |
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193 | } |
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194 | } |
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195 | } |
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196 | |||
197 | static inline void xan_wc3_output_pixel_run(XanContext *s, AVFrame *frame, |
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198 | const uint8_t *pixel_buffer, int x, int y, int pixel_count) |
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199 | { |
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200 | int stride; |
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201 | int line_inc; |
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202 | int index; |
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203 | int current_x; |
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204 | int width = s->avctx->width; |
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205 | uint8_t *palette_plane; |
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206 | |||
207 | palette_plane = frame->data[0]; |
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208 | stride = frame->linesize[0]; |
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209 | line_inc = stride - width; |
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210 | index = y * stride + x; |
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211 | current_x = x; |
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212 | while (pixel_count && index < s->frame_size) { |
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213 | int count = FFMIN(pixel_count, width - current_x); |
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214 | memcpy(palette_plane + index, pixel_buffer, count); |
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215 | pixel_count -= count; |
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216 | index += count; |
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217 | pixel_buffer += count; |
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218 | current_x += count; |
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219 | |||
220 | if (current_x >= width) { |
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221 | index += line_inc; |
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222 | current_x = 0; |
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223 | } |
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224 | } |
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225 | } |
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226 | |||
227 | static inline void xan_wc3_copy_pixel_run(XanContext *s, AVFrame *frame, |
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228 | int x, int y, |
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229 | int pixel_count, int motion_x, |
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230 | int motion_y) |
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231 | { |
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232 | int stride; |
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233 | int line_inc; |
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234 | int curframe_index, prevframe_index; |
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235 | int curframe_x, prevframe_x; |
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236 | int width = s->avctx->width; |
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237 | uint8_t *palette_plane, *prev_palette_plane; |
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238 | |||
239 | if (y + motion_y < 0 || y + motion_y >= s->avctx->height || |
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240 | x + motion_x < 0 || x + motion_x >= s->avctx->width) |
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241 | return; |
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242 | |||
243 | palette_plane = frame->data[0]; |
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244 | prev_palette_plane = s->last_frame->data[0]; |
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245 | if (!prev_palette_plane) |
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246 | prev_palette_plane = palette_plane; |
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247 | stride = frame->linesize[0]; |
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248 | line_inc = stride - width; |
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249 | curframe_index = y * stride + x; |
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250 | curframe_x = x; |
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251 | prevframe_index = (y + motion_y) * stride + x + motion_x; |
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252 | prevframe_x = x + motion_x; |
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253 | |||
254 | if (prev_palette_plane == palette_plane && FFABS(curframe_index - prevframe_index) < pixel_count) { |
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255 | avpriv_request_sample(s->avctx, "Overlapping copy\n"); |
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256 | return ; |
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257 | } |
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258 | |||
259 | while (pixel_count && |
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260 | curframe_index < s->frame_size && |
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261 | prevframe_index < s->frame_size) { |
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262 | int count = FFMIN3(pixel_count, width - curframe_x, |
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263 | width - prevframe_x); |
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264 | |||
265 | memcpy(palette_plane + curframe_index, |
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266 | prev_palette_plane + prevframe_index, count); |
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267 | pixel_count -= count; |
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268 | curframe_index += count; |
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269 | prevframe_index += count; |
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270 | curframe_x += count; |
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271 | prevframe_x += count; |
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272 | |||
273 | if (curframe_x >= width) { |
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274 | curframe_index += line_inc; |
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275 | curframe_x = 0; |
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276 | } |
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277 | |||
278 | if (prevframe_x >= width) { |
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279 | prevframe_index += line_inc; |
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280 | prevframe_x = 0; |
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281 | } |
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282 | } |
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283 | } |
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284 | |||
285 | static int xan_wc3_decode_frame(XanContext *s, AVFrame *frame) |
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286 | { |
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287 | |||
288 | int width = s->avctx->width; |
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289 | int height = s->avctx->height; |
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290 | int total_pixels = width * height; |
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291 | uint8_t opcode; |
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292 | uint8_t flag = 0; |
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293 | int size = 0; |
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294 | int motion_x, motion_y; |
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295 | int x, y, ret; |
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296 | |||
297 | uint8_t *opcode_buffer = s->buffer1; |
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298 | uint8_t *opcode_buffer_end = s->buffer1 + s->buffer1_size; |
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299 | int opcode_buffer_size = s->buffer1_size; |
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300 | const uint8_t *imagedata_buffer = s->buffer2; |
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301 | |||
302 | /* pointers to segments inside the compressed chunk */ |
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303 | const uint8_t *huffman_segment; |
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304 | GetByteContext size_segment; |
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305 | GetByteContext vector_segment; |
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306 | const uint8_t *imagedata_segment; |
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307 | int huffman_offset, size_offset, vector_offset, imagedata_offset, |
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308 | imagedata_size; |
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309 | |||
310 | if (s->size < 8) |
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311 | return AVERROR_INVALIDDATA; |
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312 | |||
313 | huffman_offset = AV_RL16(&s->buf[0]); |
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314 | size_offset = AV_RL16(&s->buf[2]); |
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315 | vector_offset = AV_RL16(&s->buf[4]); |
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316 | imagedata_offset = AV_RL16(&s->buf[6]); |
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317 | |||
318 | if (huffman_offset >= s->size || |
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319 | size_offset >= s->size || |
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320 | vector_offset >= s->size || |
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321 | imagedata_offset >= s->size) |
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322 | return AVERROR_INVALIDDATA; |
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323 | |||
324 | huffman_segment = s->buf + huffman_offset; |
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325 | bytestream2_init(&size_segment, s->buf + size_offset, s->size - size_offset); |
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326 | bytestream2_init(&vector_segment, s->buf + vector_offset, s->size - vector_offset); |
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327 | imagedata_segment = s->buf + imagedata_offset; |
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328 | |||
329 | if ((ret = xan_huffman_decode(opcode_buffer, opcode_buffer_size, |
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330 | huffman_segment, s->size - huffman_offset)) < 0) |
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331 | return AVERROR_INVALIDDATA; |
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332 | opcode_buffer_end = opcode_buffer + ret; |
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333 | |||
334 | if (imagedata_segment[0] == 2) { |
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335 | xan_unpack(s->buffer2, s->buffer2_size, |
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336 | &imagedata_segment[1], s->size - imagedata_offset - 1); |
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337 | imagedata_size = s->buffer2_size; |
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338 | } else { |
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339 | imagedata_size = s->size - imagedata_offset - 1; |
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340 | imagedata_buffer = &imagedata_segment[1]; |
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341 | } |
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342 | |||
343 | /* use the decoded data segments to build the frame */ |
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344 | x = y = 0; |
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345 | while (total_pixels && opcode_buffer < opcode_buffer_end) { |
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346 | |||
347 | opcode = *opcode_buffer++; |
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348 | size = 0; |
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349 | |||
350 | switch (opcode) { |
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351 | |||
352 | case 0: |
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353 | flag ^= 1; |
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354 | continue; |
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355 | |||
356 | case 1: |
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357 | case 2: |
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358 | case 3: |
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359 | case 4: |
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360 | case 5: |
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361 | case 6: |
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362 | case 7: |
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363 | case 8: |
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364 | size = opcode; |
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365 | break; |
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366 | |||
367 | case 12: |
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368 | case 13: |
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369 | case 14: |
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370 | case 15: |
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371 | case 16: |
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372 | case 17: |
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373 | case 18: |
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374 | size += (opcode - 10); |
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375 | break; |
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376 | |||
377 | case 9: |
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378 | case 19: |
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379 | if (bytestream2_get_bytes_left(&size_segment) < 1) { |
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380 | av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n"); |
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381 | return AVERROR_INVALIDDATA; |
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382 | } |
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383 | size = bytestream2_get_byte(&size_segment); |
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384 | break; |
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385 | |||
386 | case 10: |
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387 | case 20: |
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388 | if (bytestream2_get_bytes_left(&size_segment) < 2) { |
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389 | av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n"); |
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390 | return AVERROR_INVALIDDATA; |
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391 | } |
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392 | size = bytestream2_get_be16(&size_segment); |
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393 | break; |
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394 | |||
395 | case 11: |
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396 | case 21: |
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397 | if (bytestream2_get_bytes_left(&size_segment) < 3) { |
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398 | av_log(s->avctx, AV_LOG_ERROR, "size_segment overread\n"); |
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399 | return AVERROR_INVALIDDATA; |
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400 | } |
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401 | size = bytestream2_get_be24(&size_segment); |
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402 | break; |
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403 | } |
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404 | |||
405 | if (size > total_pixels) |
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406 | break; |
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407 | |||
408 | if (opcode < 12) { |
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409 | flag ^= 1; |
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410 | if (flag) { |
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411 | /* run of (size) pixels is unchanged from last frame */ |
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412 | xan_wc3_copy_pixel_run(s, frame, x, y, size, 0, 0); |
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413 | } else { |
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414 | /* output a run of pixels from imagedata_buffer */ |
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415 | if (imagedata_size < size) |
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416 | break; |
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417 | xan_wc3_output_pixel_run(s, frame, imagedata_buffer, x, y, size); |
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418 | imagedata_buffer += size; |
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419 | imagedata_size -= size; |
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420 | } |
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421 | } else { |
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422 | uint8_t vector; |
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423 | if (bytestream2_get_bytes_left(&vector_segment) <= 0) { |
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424 | av_log(s->avctx, AV_LOG_ERROR, "vector_segment overread\n"); |
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425 | return AVERROR_INVALIDDATA; |
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426 | } |
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427 | /* run-based motion compensation from last frame */ |
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428 | vector = bytestream2_get_byte(&vector_segment); |
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429 | motion_x = sign_extend(vector >> 4, 4); |
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430 | motion_y = sign_extend(vector & 0xF, 4); |
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431 | |||
432 | /* copy a run of pixels from the previous frame */ |
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433 | xan_wc3_copy_pixel_run(s, frame, x, y, size, motion_x, motion_y); |
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434 | |||
435 | flag = 0; |
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436 | } |
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437 | |||
438 | /* coordinate accounting */ |
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439 | total_pixels -= size; |
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440 | y += (x + size) / width; |
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441 | x = (x + size) % width; |
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442 | } |
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443 | return 0; |
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444 | } |
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445 | |||
446 | #if RUNTIME_GAMMA |
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447 | static inline unsigned mul(unsigned a, unsigned b) |
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448 | { |
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449 | return (a * b) >> 16; |
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450 | } |
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451 | |||
452 | static inline unsigned pow4(unsigned a) |
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453 | { |
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454 | unsigned square = mul(a, a); |
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455 | return mul(square, square); |
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456 | } |
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457 | |||
458 | static inline unsigned pow5(unsigned a) |
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459 | { |
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460 | return mul(pow4(a), a); |
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461 | } |
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462 | |||
463 | static uint8_t gamma_corr(uint8_t in) { |
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464 | unsigned lo, hi = 0xff40, target; |
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465 | int i = 15; |
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466 | in = (in << 2) | (in >> 6); |
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467 | /* equivalent float code: |
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468 | if (in >= 252) |
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469 | return 253; |
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470 | return round(pow(in / 256.0, 0.8) * 256); |
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471 | */ |
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472 | lo = target = in << 8; |
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473 | do { |
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474 | unsigned mid = (lo + hi) >> 1; |
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475 | unsigned pow = pow5(mid); |
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476 | if (pow > target) hi = mid; |
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477 | else lo = mid; |
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478 | } while (--i); |
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479 | return (pow4((lo + hi) >> 1) + 0x80) >> 8; |
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480 | } |
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481 | #else |
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482 | /** |
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483 | * This is a gamma correction that xan3 applies to all palette entries. |
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484 | * |
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485 | * There is a peculiarity, namely that the values are clamped to 253 - |
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486 | * it seems likely that this table was calculated by a buggy fixed-point |
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487 | * implementation, the one above under RUNTIME_GAMMA behaves like this for |
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488 | * example. |
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489 | * The exponent value of 0.8 can be explained by this as well, since 0.8 = 4/5 |
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490 | * and thus pow(x, 0.8) is still easy to calculate. |
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491 | * Also, the input values are first rotated to the left by 2. |
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492 | */ |
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493 | static const uint8_t gamma_lookup[256] = { |
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494 | 0x00, 0x09, 0x10, 0x16, 0x1C, 0x21, 0x27, 0x2C, |
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495 | 0x31, 0x35, 0x3A, 0x3F, 0x43, 0x48, 0x4C, 0x50, |
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496 | 0x54, 0x59, 0x5D, 0x61, 0x65, 0x69, 0x6D, 0x71, |
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497 | 0x75, 0x79, 0x7D, 0x80, 0x84, 0x88, 0x8C, 0x8F, |
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498 | 0x93, 0x97, 0x9A, 0x9E, 0xA2, 0xA5, 0xA9, 0xAC, |
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499 | 0xB0, 0xB3, 0xB7, 0xBA, 0xBE, 0xC1, 0xC5, 0xC8, |
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500 | 0xCB, 0xCF, 0xD2, 0xD5, 0xD9, 0xDC, 0xDF, 0xE3, |
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501 | 0xE6, 0xE9, 0xED, 0xF0, 0xF3, 0xF6, 0xFA, 0xFD, |
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502 | 0x03, 0x0B, 0x12, 0x18, 0x1D, 0x23, 0x28, 0x2D, |
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503 | 0x32, 0x36, 0x3B, 0x40, 0x44, 0x49, 0x4D, 0x51, |
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504 | 0x56, 0x5A, 0x5E, 0x62, 0x66, 0x6A, 0x6E, 0x72, |
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505 | 0x76, 0x7A, 0x7D, 0x81, 0x85, 0x89, 0x8D, 0x90, |
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506 | 0x94, 0x98, 0x9B, 0x9F, 0xA2, 0xA6, 0xAA, 0xAD, |
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507 | 0xB1, 0xB4, 0xB8, 0xBB, 0xBF, 0xC2, 0xC5, 0xC9, |
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508 | 0xCC, 0xD0, 0xD3, 0xD6, 0xDA, 0xDD, 0xE0, 0xE4, |
||
509 | 0xE7, 0xEA, 0xED, 0xF1, 0xF4, 0xF7, 0xFA, 0xFD, |
||
510 | 0x05, 0x0D, 0x13, 0x19, 0x1F, 0x24, 0x29, 0x2E, |
||
511 | 0x33, 0x38, 0x3C, 0x41, 0x45, 0x4A, 0x4E, 0x52, |
||
512 | 0x57, 0x5B, 0x5F, 0x63, 0x67, 0x6B, 0x6F, 0x73, |
||
513 | 0x77, 0x7B, 0x7E, 0x82, 0x86, 0x8A, 0x8D, 0x91, |
||
514 | 0x95, 0x99, 0x9C, 0xA0, 0xA3, 0xA7, 0xAA, 0xAE, |
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515 | 0xB2, 0xB5, 0xB9, 0xBC, 0xBF, 0xC3, 0xC6, 0xCA, |
||
516 | 0xCD, 0xD0, 0xD4, 0xD7, 0xDA, 0xDE, 0xE1, 0xE4, |
||
517 | 0xE8, 0xEB, 0xEE, 0xF1, 0xF5, 0xF8, 0xFB, 0xFD, |
||
518 | 0x07, 0x0E, 0x15, 0x1A, 0x20, 0x25, 0x2A, 0x2F, |
||
519 | 0x34, 0x39, 0x3D, 0x42, 0x46, 0x4B, 0x4F, 0x53, |
||
520 | 0x58, 0x5C, 0x60, 0x64, 0x68, 0x6C, 0x70, 0x74, |
||
521 | 0x78, 0x7C, 0x7F, 0x83, 0x87, 0x8B, 0x8E, 0x92, |
||
522 | 0x96, 0x99, 0x9D, 0xA1, 0xA4, 0xA8, 0xAB, 0xAF, |
||
523 | 0xB2, 0xB6, 0xB9, 0xBD, 0xC0, 0xC4, 0xC7, 0xCB, |
||
524 | 0xCE, 0xD1, 0xD5, 0xD8, 0xDB, 0xDF, 0xE2, 0xE5, |
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525 | 0xE9, 0xEC, 0xEF, 0xF2, 0xF6, 0xF9, 0xFC, 0xFD |
||
526 | }; |
||
527 | #endif |
||
528 | |||
529 | static int xan_decode_frame(AVCodecContext *avctx, |
||
530 | void *data, int *got_frame, |
||
531 | AVPacket *avpkt) |
||
532 | { |
||
533 | AVFrame *frame = data; |
||
534 | const uint8_t *buf = avpkt->data; |
||
535 | int ret, buf_size = avpkt->size; |
||
536 | XanContext *s = avctx->priv_data; |
||
537 | GetByteContext ctx; |
||
538 | int tag = 0; |
||
539 | |||
540 | bytestream2_init(&ctx, buf, buf_size); |
||
541 | while (bytestream2_get_bytes_left(&ctx) > 8 && tag != VGA__TAG) { |
||
542 | unsigned *tmpptr; |
||
543 | uint32_t new_pal; |
||
544 | int size; |
||
545 | int i; |
||
546 | tag = bytestream2_get_le32(&ctx); |
||
547 | size = bytestream2_get_be32(&ctx); |
||
548 | if(size < 0) { |
||
549 | av_log(avctx, AV_LOG_ERROR, "Invalid tag size %d\n", size); |
||
550 | return AVERROR_INVALIDDATA; |
||
551 | } |
||
552 | size = FFMIN(size, bytestream2_get_bytes_left(&ctx)); |
||
553 | switch (tag) { |
||
554 | case PALT_TAG: |
||
555 | if (size < PALETTE_SIZE) |
||
556 | return AVERROR_INVALIDDATA; |
||
557 | if (s->palettes_count >= PALETTES_MAX) |
||
558 | return AVERROR_INVALIDDATA; |
||
559 | tmpptr = av_realloc(s->palettes, |
||
560 | (s->palettes_count + 1) * AVPALETTE_SIZE); |
||
561 | if (!tmpptr) |
||
562 | return AVERROR(ENOMEM); |
||
563 | s->palettes = tmpptr; |
||
564 | tmpptr += s->palettes_count * AVPALETTE_COUNT; |
||
565 | for (i = 0; i < PALETTE_COUNT; i++) { |
||
566 | #if RUNTIME_GAMMA |
||
567 | int r = gamma_corr(bytestream2_get_byteu(&ctx)); |
||
568 | int g = gamma_corr(bytestream2_get_byteu(&ctx)); |
||
569 | int b = gamma_corr(bytestream2_get_byteu(&ctx)); |
||
570 | #else |
||
571 | int r = gamma_lookup[bytestream2_get_byteu(&ctx)]; |
||
572 | int g = gamma_lookup[bytestream2_get_byteu(&ctx)]; |
||
573 | int b = gamma_lookup[bytestream2_get_byteu(&ctx)]; |
||
574 | #endif |
||
575 | *tmpptr++ = (0xFFU << 24) | (r << 16) | (g << 8) | b; |
||
576 | } |
||
577 | s->palettes_count++; |
||
578 | break; |
||
579 | case SHOT_TAG: |
||
580 | if (size < 4) |
||
581 | return AVERROR_INVALIDDATA; |
||
582 | new_pal = bytestream2_get_le32(&ctx); |
||
583 | if (new_pal < s->palettes_count) { |
||
584 | s->cur_palette = new_pal; |
||
585 | } else |
||
586 | av_log(avctx, AV_LOG_ERROR, "Invalid palette selected\n"); |
||
587 | break; |
||
588 | case VGA__TAG: |
||
589 | break; |
||
590 | default: |
||
591 | bytestream2_skip(&ctx, size); |
||
592 | break; |
||
593 | } |
||
594 | } |
||
595 | buf_size = bytestream2_get_bytes_left(&ctx); |
||
596 | |||
597 | if (s->palettes_count <= 0) { |
||
598 | av_log(s->avctx, AV_LOG_ERROR, "No palette found\n"); |
||
599 | return AVERROR_INVALIDDATA; |
||
600 | } |
||
601 | |||
602 | if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) |
||
603 | return ret; |
||
604 | |||
605 | if (!s->frame_size) |
||
606 | s->frame_size = frame->linesize[0] * s->avctx->height; |
||
607 | |||
608 | memcpy(frame->data[1], |
||
609 | s->palettes + s->cur_palette * AVPALETTE_COUNT, AVPALETTE_SIZE); |
||
610 | |||
611 | s->buf = ctx.buffer; |
||
612 | s->size = buf_size; |
||
613 | |||
614 | if (xan_wc3_decode_frame(s, frame) < 0) |
||
615 | return AVERROR_INVALIDDATA; |
||
616 | |||
617 | av_frame_unref(s->last_frame); |
||
618 | if ((ret = av_frame_ref(s->last_frame, frame)) < 0) |
||
619 | return ret; |
||
620 | |||
621 | *got_frame = 1; |
||
622 | |||
623 | /* always report that the buffer was completely consumed */ |
||
624 | return buf_size; |
||
625 | } |
||
626 | |||
627 | static av_cold int xan_decode_end(AVCodecContext *avctx) |
||
628 | { |
||
629 | XanContext *s = avctx->priv_data; |
||
630 | |||
631 | av_frame_free(&s->last_frame); |
||
632 | |||
633 | av_freep(&s->buffer1); |
||
634 | av_freep(&s->buffer2); |
||
635 | av_freep(&s->palettes); |
||
636 | |||
637 | return 0; |
||
638 | } |
||
639 | |||
640 | AVCodec ff_xan_wc3_decoder = { |
||
641 | .name = "xan_wc3", |
||
642 | .long_name = NULL_IF_CONFIG_SMALL("Wing Commander III / Xan"), |
||
643 | .type = AVMEDIA_TYPE_VIDEO, |
||
644 | .id = AV_CODEC_ID_XAN_WC3, |
||
645 | .priv_data_size = sizeof(XanContext), |
||
646 | .init = xan_decode_init, |
||
647 | .close = xan_decode_end, |
||
648 | .decode = xan_decode_frame, |
||
649 | .capabilities = CODEC_CAP_DR1, |
||
650 | };>>>=>>>><>><>><>>>>><>><>=>>>>>>>>>>>>>>>>>><>>>>><>><>><>>>>> |