blob: bf4404ce4263531a53605a8cd259af3b635d5267
1 | /* |
2 | * Electronic Arts CMV Video Decoder |
3 | * Copyright (c) 2007-2008 Peter Ross |
4 | * |
5 | * This file is part of FFmpeg. |
6 | * |
7 | * FFmpeg is free software; you can redistribute it and/or |
8 | * modify it under the terms of the GNU Lesser General Public |
9 | * License as published by the Free Software Foundation; either |
10 | * version 2.1 of the License, or (at your option) any later version. |
11 | * |
12 | * FFmpeg is distributed in the hope that it will be useful, |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 | * Lesser General Public License for more details. |
16 | * |
17 | * You should have received a copy of the GNU Lesser General Public |
18 | * License along with FFmpeg; if not, write to the Free Software |
19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
20 | */ |
21 | |
22 | /** |
23 | * @file |
24 | * Electronic Arts CMV Video Decoder |
25 | * by Peter Ross (pross@xvid.org) |
26 | * |
27 | * Technical details here: |
28 | * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_CMV |
29 | */ |
30 | |
31 | #include "libavutil/common.h" |
32 | #include "libavutil/intreadwrite.h" |
33 | #include "libavutil/imgutils.h" |
34 | #include "avcodec.h" |
35 | #include "internal.h" |
36 | |
37 | typedef struct CmvContext { |
38 | AVCodecContext *avctx; |
39 | AVFrame *last_frame; ///< last |
40 | AVFrame *last2_frame; ///< second-last |
41 | int width, height; |
42 | unsigned int palette[AVPALETTE_COUNT]; |
43 | } CmvContext; |
44 | |
45 | static av_cold int cmv_decode_init(AVCodecContext *avctx){ |
46 | CmvContext *s = avctx->priv_data; |
47 | |
48 | s->avctx = avctx; |
49 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
50 | |
51 | s->last_frame = av_frame_alloc(); |
52 | s->last2_frame = av_frame_alloc(); |
53 | if (!s->last_frame || !s->last2_frame) { |
54 | av_frame_free(&s->last_frame); |
55 | av_frame_free(&s->last2_frame); |
56 | return AVERROR(ENOMEM); |
57 | } |
58 | |
59 | return 0; |
60 | } |
61 | |
62 | static void cmv_decode_intra(CmvContext * s, AVFrame *frame, |
63 | const uint8_t *buf, const uint8_t *buf_end) |
64 | { |
65 | unsigned char *dst = frame->data[0]; |
66 | int i; |
67 | |
68 | for (i=0; i < s->avctx->height && buf_end - buf >= s->avctx->width; i++) { |
69 | memcpy(dst, buf, s->avctx->width); |
70 | dst += frame->linesize[0]; |
71 | buf += s->avctx->width; |
72 | } |
73 | } |
74 | |
75 | static void cmv_motcomp(unsigned char *dst, ptrdiff_t dst_stride, |
76 | const unsigned char *src, ptrdiff_t src_stride, |
77 | int x, int y, |
78 | int xoffset, int yoffset, |
79 | int width, int height){ |
80 | int i,j; |
81 | |
82 | for(j=y;j<y+4;j++) |
83 | for(i=x;i<x+4;i++) |
84 | { |
85 | if (i+xoffset>=0 && i+xoffset<width && |
86 | j+yoffset>=0 && j+yoffset<height) { |
87 | dst[j*dst_stride + i] = src[(j+yoffset)*src_stride + i+xoffset]; |
88 | }else{ |
89 | dst[j*dst_stride + i] = 0; |
90 | } |
91 | } |
92 | } |
93 | |
94 | static void cmv_decode_inter(CmvContext *s, AVFrame *frame, const uint8_t *buf, |
95 | const uint8_t *buf_end) |
96 | { |
97 | const uint8_t *raw = buf + (s->avctx->width*s->avctx->height/16); |
98 | int x,y,i; |
99 | |
100 | i = 0; |
101 | for(y=0; y<s->avctx->height/4; y++) |
102 | for(x=0; x<s->avctx->width/4 && buf_end - buf > i; x++) { |
103 | if (buf[i]==0xFF) { |
104 | unsigned char *dst = frame->data[0] + (y*4)*frame->linesize[0] + x*4; |
105 | if (raw+16<buf_end && *raw==0xFF) { /* intra */ |
106 | raw++; |
107 | memcpy(dst, raw, 4); |
108 | memcpy(dst + frame->linesize[0], raw+4, 4); |
109 | memcpy(dst + 2 * frame->linesize[0], raw+8, 4); |
110 | memcpy(dst + 3 * frame->linesize[0], raw+12, 4); |
111 | raw+=16; |
112 | }else if(raw<buf_end) { /* inter using second-last frame as reference */ |
113 | int xoffset = (*raw & 0xF) - 7; |
114 | int yoffset = ((*raw >> 4)) - 7; |
115 | if (s->last2_frame->data[0]) |
116 | cmv_motcomp(frame->data[0], frame->linesize[0], |
117 | s->last2_frame->data[0], s->last2_frame->linesize[0], |
118 | x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height); |
119 | raw++; |
120 | } |
121 | }else{ /* inter using last frame as reference */ |
122 | int xoffset = (buf[i] & 0xF) - 7; |
123 | int yoffset = ((buf[i] >> 4)) - 7; |
124 | if (s->last_frame->data[0]) |
125 | cmv_motcomp(frame->data[0], frame->linesize[0], |
126 | s->last_frame->data[0], s->last_frame->linesize[0], |
127 | x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height); |
128 | } |
129 | i++; |
130 | } |
131 | } |
132 | |
133 | static int cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end) |
134 | { |
135 | int pal_start, pal_count, i, ret, fps; |
136 | |
137 | if(buf_end - buf < 16) { |
138 | av_log(s->avctx, AV_LOG_WARNING, "truncated header\n"); |
139 | return AVERROR_INVALIDDATA; |
140 | } |
141 | |
142 | s->width = AV_RL16(&buf[4]); |
143 | s->height = AV_RL16(&buf[6]); |
144 | |
145 | if (s->width != s->avctx->width || |
146 | s->height != s->avctx->height) { |
147 | av_frame_unref(s->last_frame); |
148 | av_frame_unref(s->last2_frame); |
149 | } |
150 | |
151 | ret = ff_set_dimensions(s->avctx, s->width, s->height); |
152 | if (ret < 0) |
153 | return ret; |
154 | |
155 | fps = AV_RL16(&buf[10]); |
156 | if (fps > 0) |
157 | s->avctx->framerate = (AVRational){ fps, 1 }; |
158 | |
159 | pal_start = AV_RL16(&buf[12]); |
160 | pal_count = AV_RL16(&buf[14]); |
161 | |
162 | buf += 16; |
163 | for (i=pal_start; i<pal_start+pal_count && i<AVPALETTE_COUNT && buf_end - buf >= 3; i++) { |
164 | s->palette[i] = 0xFFU << 24 | AV_RB24(buf); |
165 | buf += 3; |
166 | } |
167 | |
168 | return 0; |
169 | } |
170 | |
171 | #define EA_PREAMBLE_SIZE 8 |
172 | #define MVIh_TAG MKTAG('M', 'V', 'I', 'h') |
173 | |
174 | static int cmv_decode_frame(AVCodecContext *avctx, |
175 | void *data, int *got_frame, |
176 | AVPacket *avpkt) |
177 | { |
178 | const uint8_t *buf = avpkt->data; |
179 | int buf_size = avpkt->size; |
180 | CmvContext *s = avctx->priv_data; |
181 | const uint8_t *buf_end = buf + buf_size; |
182 | AVFrame *frame = data; |
183 | int ret; |
184 | |
185 | if (buf_end - buf < EA_PREAMBLE_SIZE) |
186 | return AVERROR_INVALIDDATA; |
187 | |
188 | if (AV_RL32(buf)==MVIh_TAG||AV_RB32(buf)==MVIh_TAG) { |
189 | unsigned size = AV_RL32(buf + 4); |
190 | ret = cmv_process_header(s, buf+EA_PREAMBLE_SIZE, buf_end); |
191 | if (ret < 0) |
192 | return ret; |
193 | if (size > buf_end - buf - EA_PREAMBLE_SIZE) |
194 | return -1; |
195 | buf += size; |
196 | } |
197 | |
198 | if (av_image_check_size(s->width, s->height, 0, s->avctx)) |
199 | return -1; |
200 | |
201 | if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) |
202 | return ret; |
203 | |
204 | memcpy(frame->data[1], s->palette, AVPALETTE_SIZE); |
205 | |
206 | buf += EA_PREAMBLE_SIZE; |
207 | if ((buf[0]&1)) { // subtype |
208 | cmv_decode_inter(s, frame, buf+2, buf_end); |
209 | frame->key_frame = 0; |
210 | frame->pict_type = AV_PICTURE_TYPE_P; |
211 | }else{ |
212 | frame->key_frame = 1; |
213 | frame->pict_type = AV_PICTURE_TYPE_I; |
214 | cmv_decode_intra(s, frame, buf+2, buf_end); |
215 | } |
216 | |
217 | av_frame_unref(s->last2_frame); |
218 | av_frame_move_ref(s->last2_frame, s->last_frame); |
219 | if ((ret = av_frame_ref(s->last_frame, frame)) < 0) |
220 | return ret; |
221 | |
222 | *got_frame = 1; |
223 | |
224 | return buf_size; |
225 | } |
226 | |
227 | static av_cold int cmv_decode_end(AVCodecContext *avctx){ |
228 | CmvContext *s = avctx->priv_data; |
229 | |
230 | av_frame_free(&s->last_frame); |
231 | av_frame_free(&s->last2_frame); |
232 | |
233 | return 0; |
234 | } |
235 | |
236 | AVCodec ff_eacmv_decoder = { |
237 | .name = "eacmv", |
238 | .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts CMV video"), |
239 | .type = AVMEDIA_TYPE_VIDEO, |
240 | .id = AV_CODEC_ID_CMV, |
241 | .priv_data_size = sizeof(CmvContext), |
242 | .init = cmv_decode_init, |
243 | .close = cmv_decode_end, |
244 | .decode = cmv_decode_frame, |
245 | .capabilities = AV_CODEC_CAP_DR1, |
246 | }; |
247 |