| 1 | /* |
| 2 | * Creative YUV (CYUV) Video Decoder |
| 3 | * by Mike Melanson (melanson@pcisys.net) |
| 4 | * based on "Creative YUV (CYUV) stream format for AVI": |
| 5 | * http://www.csse.monash.edu.au/~timf/videocodec/cyuv.txt |
| 6 | * |
| 7 | * Copyright (c) 2003 The FFmpeg Project |
| 8 | * |
| 9 | * This file is part of FFmpeg. |
| 10 | * |
| 11 | * FFmpeg is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU Lesser General Public |
| 13 | * License as published by the Free Software Foundation; either |
| 14 | * version 2.1 of the License, or (at your option) any later version. |
| 15 | * |
| 16 | * FFmpeg is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 19 | * Lesser General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU Lesser General Public |
| 22 | * License along with FFmpeg; if not, write to the Free Software |
| 23 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 24 | */ |
| 25 | |
| 26 | /** |
| 27 | * @file |
| 28 | * Creative YUV (CYUV) Video Decoder. |
| 29 | */ |
| 30 | |
| 31 | #include <stdio.h> |
| 32 | #include <stdlib.h> |
| 33 | #include <string.h> |
| 34 | |
| 35 | #include "avcodec.h" |
| 36 | #include "internal.h" |
| 37 | #include "libavutil/internal.h" |
| 38 | |
| 39 | |
| 40 | typedef struct CyuvDecodeContext { |
| 41 | AVCodecContext *avctx; |
| 42 | int width, height; |
| 43 | } CyuvDecodeContext; |
| 44 | |
| 45 | static av_cold int cyuv_decode_init(AVCodecContext *avctx) |
| 46 | { |
| 47 | CyuvDecodeContext *s = avctx->priv_data; |
| 48 | |
| 49 | s->avctx = avctx; |
| 50 | s->width = avctx->width; |
| 51 | /* width needs to be divisible by 4 for this codec to work */ |
| 52 | if (s->width & 0x3) |
| 53 | return AVERROR_INVALIDDATA; |
| 54 | s->height = avctx->height; |
| 55 | |
| 56 | return 0; |
| 57 | } |
| 58 | |
| 59 | static int cyuv_decode_frame(AVCodecContext *avctx, |
| 60 | void *data, int *got_frame, |
| 61 | AVPacket *avpkt) |
| 62 | { |
| 63 | const uint8_t *buf = avpkt->data; |
| 64 | int buf_size = avpkt->size; |
| 65 | CyuvDecodeContext *s=avctx->priv_data; |
| 66 | AVFrame *frame = data; |
| 67 | |
| 68 | unsigned char *y_plane; |
| 69 | unsigned char *u_plane; |
| 70 | unsigned char *v_plane; |
| 71 | int y_ptr; |
| 72 | int u_ptr; |
| 73 | int v_ptr; |
| 74 | |
| 75 | /* prediction error tables (make it clear that they are signed values) */ |
| 76 | const signed char *y_table = (const signed char*)buf + 0; |
| 77 | const signed char *u_table = (const signed char*)buf + 16; |
| 78 | const signed char *v_table = (const signed char*)buf + 32; |
| 79 | |
| 80 | unsigned char y_pred, u_pred, v_pred; |
| 81 | int stream_ptr; |
| 82 | unsigned char cur_byte; |
| 83 | int pixel_groups; |
| 84 | int rawsize = s->height * FFALIGN(s->width,2) * 2; |
| 85 | int ret; |
| 86 | |
| 87 | if (avctx->codec_id == AV_CODEC_ID_AURA) { |
| 88 | y_table = u_table; |
| 89 | u_table = v_table; |
| 90 | } |
| 91 | /* sanity check the buffer size: A buffer has 3x16-bytes tables |
| 92 | * followed by (height) lines each with 3 bytes to represent groups |
| 93 | * of 4 pixels. Thus, the total size of the buffer ought to be: |
| 94 | * (3 * 16) + height * (width * 3 / 4) */ |
| 95 | if (buf_size == 48 + s->height * (s->width * 3 / 4)) { |
| 96 | avctx->pix_fmt = AV_PIX_FMT_YUV411P; |
| 97 | } else if(buf_size == rawsize ) { |
| 98 | avctx->pix_fmt = AV_PIX_FMT_UYVY422; |
| 99 | } else { |
| 100 | av_log(avctx, AV_LOG_ERROR, "got a buffer with %d bytes when %d were expected\n", |
| 101 | buf_size, 48 + s->height * (s->width * 3 / 4)); |
| 102 | return AVERROR_INVALIDDATA; |
| 103 | } |
| 104 | |
| 105 | /* pixel data starts 48 bytes in, after 3x16-byte tables */ |
| 106 | stream_ptr = 48; |
| 107 | |
| 108 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
| 109 | return ret; |
| 110 | |
| 111 | y_plane = frame->data[0]; |
| 112 | u_plane = frame->data[1]; |
| 113 | v_plane = frame->data[2]; |
| 114 | |
| 115 | if (buf_size == rawsize) { |
| 116 | int linesize = FFALIGN(s->width,2) * 2; |
| 117 | y_plane += frame->linesize[0] * s->height; |
| 118 | for (stream_ptr = 0; stream_ptr < rawsize; stream_ptr += linesize) { |
| 119 | y_plane -= frame->linesize[0]; |
| 120 | memcpy(y_plane, buf+stream_ptr, linesize); |
| 121 | } |
| 122 | } else { |
| 123 | |
| 124 | /* iterate through each line in the height */ |
| 125 | for (y_ptr = 0, u_ptr = 0, v_ptr = 0; |
| 126 | y_ptr < (s->height * frame->linesize[0]); |
| 127 | y_ptr += frame->linesize[0] - s->width, |
| 128 | u_ptr += frame->linesize[1] - s->width / 4, |
| 129 | v_ptr += frame->linesize[2] - s->width / 4) { |
| 130 | |
| 131 | /* reset predictors */ |
| 132 | cur_byte = buf[stream_ptr++]; |
| 133 | u_plane[u_ptr++] = u_pred = cur_byte & 0xF0; |
| 134 | y_plane[y_ptr++] = y_pred = (cur_byte & 0x0F) << 4; |
| 135 | |
| 136 | cur_byte = buf[stream_ptr++]; |
| 137 | v_plane[v_ptr++] = v_pred = cur_byte & 0xF0; |
| 138 | y_pred += y_table[cur_byte & 0x0F]; |
| 139 | y_plane[y_ptr++] = y_pred; |
| 140 | |
| 141 | cur_byte = buf[stream_ptr++]; |
| 142 | y_pred += y_table[cur_byte & 0x0F]; |
| 143 | y_plane[y_ptr++] = y_pred; |
| 144 | y_pred += y_table[(cur_byte & 0xF0) >> 4]; |
| 145 | y_plane[y_ptr++] = y_pred; |
| 146 | |
| 147 | /* iterate through the remaining pixel groups (4 pixels/group) */ |
| 148 | pixel_groups = s->width / 4 - 1; |
| 149 | while (pixel_groups--) { |
| 150 | |
| 151 | cur_byte = buf[stream_ptr++]; |
| 152 | u_pred += u_table[(cur_byte & 0xF0) >> 4]; |
| 153 | u_plane[u_ptr++] = u_pred; |
| 154 | y_pred += y_table[cur_byte & 0x0F]; |
| 155 | y_plane[y_ptr++] = y_pred; |
| 156 | |
| 157 | cur_byte = buf[stream_ptr++]; |
| 158 | v_pred += v_table[(cur_byte & 0xF0) >> 4]; |
| 159 | v_plane[v_ptr++] = v_pred; |
| 160 | y_pred += y_table[cur_byte & 0x0F]; |
| 161 | y_plane[y_ptr++] = y_pred; |
| 162 | |
| 163 | cur_byte = buf[stream_ptr++]; |
| 164 | y_pred += y_table[cur_byte & 0x0F]; |
| 165 | y_plane[y_ptr++] = y_pred; |
| 166 | y_pred += y_table[(cur_byte & 0xF0) >> 4]; |
| 167 | y_plane[y_ptr++] = y_pred; |
| 168 | |
| 169 | } |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | *got_frame = 1; |
| 174 | |
| 175 | return buf_size; |
| 176 | } |
| 177 | |
| 178 | #if CONFIG_AURA_DECODER |
| 179 | AVCodec ff_aura_decoder = { |
| 180 | .name = "aura", |
| 181 | .long_name = NULL_IF_CONFIG_SMALL("Auravision AURA"), |
| 182 | .type = AVMEDIA_TYPE_VIDEO, |
| 183 | .id = AV_CODEC_ID_AURA, |
| 184 | .priv_data_size = sizeof(CyuvDecodeContext), |
| 185 | .init = cyuv_decode_init, |
| 186 | .decode = cyuv_decode_frame, |
| 187 | .capabilities = CODEC_CAP_DR1, |
| 188 | }; |
| 189 | #endif |
| 190 | |
| 191 | #if CONFIG_CYUV_DECODER |
| 192 | AVCodec ff_cyuv_decoder = { |
| 193 | .name = "cyuv", |
| 194 | .long_name = NULL_IF_CONFIG_SMALL("Creative YUV (CYUV)"), |
| 195 | .type = AVMEDIA_TYPE_VIDEO, |
| 196 | .id = AV_CODEC_ID_CYUV, |
| 197 | .priv_data_size = sizeof(CyuvDecodeContext), |
| 198 | .init = cyuv_decode_init, |
| 199 | .decode = cyuv_decode_frame, |
| 200 | .capabilities = CODEC_CAP_DR1, |
| 201 | }; |
| 202 | #endif |