| 1 | /* |
| 2 | * Psygnosis YOP decoder |
| 3 | * |
| 4 | * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com> |
| 5 | * derived from the code by |
| 6 | * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com> |
| 7 | * |
| 8 | * This file is part of FFmpeg. |
| 9 | * |
| 10 | * FFmpeg is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU Lesser General Public |
| 12 | * License as published by the Free Software Foundation; either |
| 13 | * version 2.1 of the License, or (at your option) any later version. |
| 14 | * |
| 15 | * FFmpeg is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * Lesser General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU Lesser General Public |
| 21 | * License along with FFmpeg; if not, write to the Free Software |
| 22 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 23 | */ |
| 24 | |
| 25 | #include "libavutil/intreadwrite.h" |
| 26 | #include "libavutil/imgutils.h" |
| 27 | |
| 28 | #include "avcodec.h" |
| 29 | #include "get_bits.h" |
| 30 | #include "internal.h" |
| 31 | |
| 32 | typedef struct YopDecContext { |
| 33 | AVCodecContext *avctx; |
| 34 | AVFrame *frame; |
| 35 | |
| 36 | int num_pal_colors; |
| 37 | int first_color[2]; |
| 38 | int frame_data_length; |
| 39 | |
| 40 | uint8_t *low_nibble; |
| 41 | uint8_t *srcptr; |
| 42 | uint8_t *src_end; |
| 43 | uint8_t *dstptr; |
| 44 | uint8_t *dstbuf; |
| 45 | } YopDecContext; |
| 46 | |
| 47 | // These tables are taken directly from: |
| 48 | // http://wiki.multimedia.cx/index.php?title=Psygnosis_YOP |
| 49 | |
| 50 | /** |
| 51 | * Lookup table for painting macroblocks. Bytes 0-2 of each entry contain |
| 52 | * the macroblock positions to be painted (taken as (0, B0, B1, B2)). |
| 53 | * Byte 3 contains the number of bytes consumed on the input, |
| 54 | * equal to max(bytes 0-2) + 1. |
| 55 | */ |
| 56 | static const uint8_t paint_lut[15][4] = |
| 57 | {{1, 2, 3, 4}, {1, 2, 0, 3}, |
| 58 | {1, 2, 1, 3}, {1, 2, 2, 3}, |
| 59 | {1, 0, 2, 3}, {1, 0, 0, 2}, |
| 60 | {1, 0, 1, 2}, {1, 1, 2, 3}, |
| 61 | {0, 1, 2, 3}, {0, 1, 0, 2}, |
| 62 | {1, 1, 0, 2}, {0, 1, 1, 2}, |
| 63 | {0, 0, 1, 2}, {0, 0, 0, 1}, |
| 64 | {1, 1, 1, 2}, |
| 65 | }; |
| 66 | |
| 67 | /** |
| 68 | * Lookup table for copying macroblocks. Each entry contains the respective |
| 69 | * x and y pixel offset for the copy source. |
| 70 | */ |
| 71 | static const int8_t motion_vector[16][2] = |
| 72 | {{-4, -4}, {-2, -4}, |
| 73 | { 0, -4}, { 2, -4}, |
| 74 | {-4, -2}, {-4, 0}, |
| 75 | {-3, -3}, {-1, -3}, |
| 76 | { 1, -3}, { 3, -3}, |
| 77 | {-3, -1}, {-2, -2}, |
| 78 | { 0, -2}, { 2, -2}, |
| 79 | { 4, -2}, {-2, 0}, |
| 80 | }; |
| 81 | |
| 82 | static av_cold int yop_decode_close(AVCodecContext *avctx) |
| 83 | { |
| 84 | YopDecContext *s = avctx->priv_data; |
| 85 | |
| 86 | av_frame_free(&s->frame); |
| 87 | |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | static av_cold int yop_decode_init(AVCodecContext *avctx) |
| 92 | { |
| 93 | YopDecContext *s = avctx->priv_data; |
| 94 | s->avctx = avctx; |
| 95 | |
| 96 | if (avctx->width & 1 || avctx->height & 1 || |
| 97 | av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) { |
| 98 | av_log(avctx, AV_LOG_ERROR, "YOP has invalid dimensions\n"); |
| 99 | return AVERROR_INVALIDDATA; |
| 100 | } |
| 101 | |
| 102 | if (avctx->extradata_size < 3) { |
| 103 | av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata.\n"); |
| 104 | return AVERROR_INVALIDDATA; |
| 105 | } |
| 106 | |
| 107 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| 108 | |
| 109 | s->num_pal_colors = avctx->extradata[0]; |
| 110 | s->first_color[0] = avctx->extradata[1]; |
| 111 | s->first_color[1] = avctx->extradata[2]; |
| 112 | |
| 113 | if (s->num_pal_colors + s->first_color[0] > 256 || |
| 114 | s->num_pal_colors + s->first_color[1] > 256) { |
| 115 | av_log(avctx, AV_LOG_ERROR, |
| 116 | "Palette parameters invalid, header probably corrupt\n"); |
| 117 | return AVERROR_INVALIDDATA; |
| 118 | } |
| 119 | |
| 120 | s->frame = av_frame_alloc(); |
| 121 | if (!s->frame) |
| 122 | return AVERROR(ENOMEM); |
| 123 | |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * Paint a macroblock using the pattern in paint_lut. |
| 129 | * @param s codec context |
| 130 | * @param tag the tag that was in the nibble |
| 131 | */ |
| 132 | static int yop_paint_block(YopDecContext *s, int linesize, int tag) |
| 133 | { |
| 134 | if (s->src_end - s->srcptr < paint_lut[tag][3]) { |
| 135 | av_log(s->avctx, AV_LOG_ERROR, "Packet too small.\n"); |
| 136 | return AVERROR_INVALIDDATA; |
| 137 | } |
| 138 | |
| 139 | s->dstptr[0] = s->srcptr[0]; |
| 140 | s->dstptr[1] = s->srcptr[paint_lut[tag][0]]; |
| 141 | s->dstptr[linesize] = s->srcptr[paint_lut[tag][1]]; |
| 142 | s->dstptr[linesize + 1] = s->srcptr[paint_lut[tag][2]]; |
| 143 | |
| 144 | // The number of src bytes consumed is in the last part of the lut entry. |
| 145 | s->srcptr += paint_lut[tag][3]; |
| 146 | return 0; |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * Copy a previously painted macroblock to the current_block. |
| 151 | * @param copy_tag the tag that was in the nibble |
| 152 | */ |
| 153 | static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag) |
| 154 | { |
| 155 | uint8_t *bufptr; |
| 156 | |
| 157 | // Calculate position for the copy source |
| 158 | bufptr = s->dstptr + motion_vector[copy_tag][0] + |
| 159 | linesize * motion_vector[copy_tag][1]; |
| 160 | if (bufptr < s->dstbuf) { |
| 161 | av_log(s->avctx, AV_LOG_ERROR, "File probably corrupt\n"); |
| 162 | return AVERROR_INVALIDDATA; |
| 163 | } |
| 164 | |
| 165 | s->dstptr[0] = bufptr[0]; |
| 166 | s->dstptr[1] = bufptr[1]; |
| 167 | s->dstptr[linesize] = bufptr[linesize]; |
| 168 | s->dstptr[linesize + 1] = bufptr[linesize + 1]; |
| 169 | |
| 170 | return 0; |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * Return the next nibble in sequence, consuming a new byte on the input |
| 175 | * only if necessary. |
| 176 | */ |
| 177 | static uint8_t yop_get_next_nibble(YopDecContext *s) |
| 178 | { |
| 179 | int ret; |
| 180 | |
| 181 | if (s->low_nibble) { |
| 182 | ret = *s->low_nibble & 0xf; |
| 183 | s->low_nibble = NULL; |
| 184 | }else { |
| 185 | s->low_nibble = s->srcptr++; |
| 186 | ret = *s->low_nibble >> 4; |
| 187 | } |
| 188 | return ret; |
| 189 | } |
| 190 | |
| 191 | static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, |
| 192 | AVPacket *avpkt) |
| 193 | { |
| 194 | YopDecContext *s = avctx->priv_data; |
| 195 | AVFrame *frame = s->frame; |
| 196 | int tag, firstcolor, is_odd_frame; |
| 197 | int ret, i, x, y; |
| 198 | uint32_t *palette; |
| 199 | |
| 200 | if (avpkt->size < 4 + 3 * s->num_pal_colors) { |
| 201 | av_log(avctx, AV_LOG_ERROR, "Packet too small.\n"); |
| 202 | return AVERROR_INVALIDDATA; |
| 203 | } |
| 204 | |
| 205 | if ((ret = ff_reget_buffer(avctx, frame)) < 0) |
| 206 | return ret; |
| 207 | |
| 208 | if (!avctx->frame_number) |
| 209 | memset(frame->data[1], 0, AVPALETTE_SIZE); |
| 210 | |
| 211 | s->dstbuf = frame->data[0]; |
| 212 | s->dstptr = frame->data[0]; |
| 213 | s->srcptr = avpkt->data + 4; |
| 214 | s->src_end = avpkt->data + avpkt->size; |
| 215 | s->low_nibble = NULL; |
| 216 | |
| 217 | is_odd_frame = avpkt->data[0]; |
| 218 | if(is_odd_frame>1){ |
| 219 | av_log(avctx, AV_LOG_ERROR, "frame is too odd %d\n", is_odd_frame); |
| 220 | return AVERROR_INVALIDDATA; |
| 221 | } |
| 222 | firstcolor = s->first_color[is_odd_frame]; |
| 223 | palette = (uint32_t *)frame->data[1]; |
| 224 | |
| 225 | for (i = 0; i < s->num_pal_colors; i++, s->srcptr += 3) { |
| 226 | palette[i + firstcolor] = (s->srcptr[0] << 18) | |
| 227 | (s->srcptr[1] << 10) | |
| 228 | (s->srcptr[2] << 2); |
| 229 | palette[i + firstcolor] |= 0xFFU << 24 | |
| 230 | (palette[i + firstcolor] >> 6) & 0x30303; |
| 231 | } |
| 232 | |
| 233 | frame->palette_has_changed = 1; |
| 234 | |
| 235 | for (y = 0; y < avctx->height; y += 2) { |
| 236 | for (x = 0; x < avctx->width; x += 2) { |
| 237 | if (s->srcptr - avpkt->data >= avpkt->size) { |
| 238 | av_log(avctx, AV_LOG_ERROR, "Packet too small.\n"); |
| 239 | return AVERROR_INVALIDDATA; |
| 240 | } |
| 241 | |
| 242 | tag = yop_get_next_nibble(s); |
| 243 | |
| 244 | if (tag != 0xf) { |
| 245 | ret = yop_paint_block(s, frame->linesize[0], tag); |
| 246 | if (ret < 0) |
| 247 | return ret; |
| 248 | } else { |
| 249 | tag = yop_get_next_nibble(s); |
| 250 | ret = yop_copy_previous_block(s, frame->linesize[0], tag); |
| 251 | if (ret < 0) |
| 252 | return ret; |
| 253 | } |
| 254 | s->dstptr += 2; |
| 255 | } |
| 256 | s->dstptr += 2*frame->linesize[0] - x; |
| 257 | } |
| 258 | |
| 259 | if ((ret = av_frame_ref(data, s->frame)) < 0) |
| 260 | return ret; |
| 261 | |
| 262 | *got_frame = 1; |
| 263 | return avpkt->size; |
| 264 | } |
| 265 | |
| 266 | AVCodec ff_yop_decoder = { |
| 267 | .name = "yop", |
| 268 | .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP Video"), |
| 269 | .type = AVMEDIA_TYPE_VIDEO, |
| 270 | .id = AV_CODEC_ID_YOP, |
| 271 | .priv_data_size = sizeof(YopDecContext), |
| 272 | .init = yop_decode_init, |
| 273 | .close = yop_decode_close, |
| 274 | .decode = yop_decode_frame, |
| 275 | }; |