lavc decoders: work with refcounted frames.
[libav.git] / libavcodec / eacmv.c
1 /*
2 * Electronic Arts CMV Video Decoder
3 * Copyright (c) 2007-2008 Peter Ross
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; 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 s->avctx = avctx;
48 avctx->pix_fmt = AV_PIX_FMT_PAL8;
49
50 s->last_frame = av_frame_alloc();
51 s->last2_frame = av_frame_alloc();
52 if (!s->last_frame || !s->last2_frame) {
53 av_frame_free(&s->last_frame);
54 av_frame_free(&s->last2_frame);
55 return AVERROR(ENOMEM);
56 }
57
58 return 0;
59 }
60
61 static void cmv_decode_intra(CmvContext * s, AVFrame *frame,
62 const uint8_t *buf, const uint8_t *buf_end)
63 {
64 unsigned char *dst = frame->data[0];
65 int i;
66
67 for (i=0; i < s->avctx->height && buf_end - buf >= s->avctx->width; i++) {
68 memcpy(dst, buf, s->avctx->width);
69 dst += frame->linesize[0];
70 buf += s->avctx->width;
71 }
72 }
73
74 static void cmv_motcomp(unsigned char *dst, int dst_stride,
75 const unsigned char *src, int src_stride,
76 int x, int y,
77 int xoffset, int yoffset,
78 int width, int height){
79 int i,j;
80
81 for(j=y;j<y+4;j++)
82 for(i=x;i<x+4;i++)
83 {
84 if (i+xoffset>=0 && i+xoffset<width &&
85 j+yoffset>=0 && j+yoffset<height) {
86 dst[j*dst_stride + i] = src[(j+yoffset)*src_stride + i+xoffset];
87 }else{
88 dst[j*dst_stride + i] = 0;
89 }
90 }
91 }
92
93 static void cmv_decode_inter(CmvContext *s, AVFrame *frame, const uint8_t *buf,
94 const uint8_t *buf_end)
95 {
96 const uint8_t *raw = buf + (s->avctx->width*s->avctx->height/16);
97 int x,y,i;
98
99 i = 0;
100 for(y=0; y<s->avctx->height/4; y++)
101 for(x=0; x<s->avctx->width/4 && buf_end - buf > i; x++) {
102 if (buf[i]==0xFF) {
103 unsigned char *dst = frame->data[0] + (y*4)*frame->linesize[0] + x*4;
104 if (raw+16<buf_end && *raw==0xFF) { /* intra */
105 raw++;
106 memcpy(dst, raw, 4);
107 memcpy(dst + frame->linesize[0], raw+4, 4);
108 memcpy(dst + 2 * frame->linesize[0], raw+8, 4);
109 memcpy(dst + 3 * frame->linesize[0], raw+12, 4);
110 raw+=16;
111 }else if(raw<buf_end) { /* inter using second-last frame as reference */
112 int xoffset = (*raw & 0xF) - 7;
113 int yoffset = ((*raw >> 4)) - 7;
114 if (s->last2_frame->data[0])
115 cmv_motcomp(frame->data[0], frame->linesize[0],
116 s->last2_frame->data[0], s->last2_frame->linesize[0],
117 x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height);
118 raw++;
119 }
120 }else{ /* inter using last frame as reference */
121 int xoffset = (buf[i] & 0xF) - 7;
122 int yoffset = ((buf[i] >> 4)) - 7;
123 cmv_motcomp(frame->data[0], frame->linesize[0],
124 s->last_frame->data[0], s->last_frame->linesize[0],
125 x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height);
126 }
127 i++;
128 }
129 }
130
131 static void cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end)
132 {
133 int pal_start, pal_count, i;
134
135 if(buf_end - buf < 16) {
136 av_log(s->avctx, AV_LOG_WARNING, "truncated header\n");
137 return;
138 }
139
140 s->width = AV_RL16(&buf[4]);
141 s->height = AV_RL16(&buf[6]);
142 if (s->avctx->width!=s->width || s->avctx->height!=s->height)
143 avcodec_set_dimensions(s->avctx, s->width, s->height);
144
145 s->avctx->time_base.num = 1;
146 s->avctx->time_base.den = AV_RL16(&buf[10]);
147
148 pal_start = AV_RL16(&buf[12]);
149 pal_count = AV_RL16(&buf[14]);
150
151 buf += 16;
152 for (i=pal_start; i<pal_start+pal_count && i<AVPALETTE_COUNT && buf_end - buf >= 3; i++) {
153 s->palette[i] = AV_RB24(buf);
154 buf += 3;
155 }
156 }
157
158 #define EA_PREAMBLE_SIZE 8
159 #define MVIh_TAG MKTAG('M', 'V', 'I', 'h')
160
161 static int cmv_decode_frame(AVCodecContext *avctx,
162 void *data, int *got_frame,
163 AVPacket *avpkt)
164 {
165 const uint8_t *buf = avpkt->data;
166 int buf_size = avpkt->size;
167 CmvContext *s = avctx->priv_data;
168 const uint8_t *buf_end = buf + buf_size;
169 AVFrame *frame = data;
170 int ret;
171
172 if (buf_end - buf < EA_PREAMBLE_SIZE)
173 return AVERROR_INVALIDDATA;
174
175 if (AV_RL32(buf)==MVIh_TAG||AV_RB32(buf)==MVIh_TAG) {
176 cmv_process_header(s, buf+EA_PREAMBLE_SIZE, buf_end);
177 return buf_size;
178 }
179
180 if (av_image_check_size(s->width, s->height, 0, s->avctx))
181 return -1;
182
183 if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
184 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
185 return ret;
186 }
187
188 memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
189
190 buf += EA_PREAMBLE_SIZE;
191 if ((buf[0]&1)) { // subtype
192 cmv_decode_inter(s, frame, buf+2, buf_end);
193 frame->key_frame = 0;
194 frame->pict_type = AV_PICTURE_TYPE_P;
195 }else{
196 frame->key_frame = 1;
197 frame->pict_type = AV_PICTURE_TYPE_I;
198 cmv_decode_intra(s, frame, buf+2, buf_end);
199 }
200
201 av_frame_unref(s->last2_frame);
202 av_frame_move_ref(s->last2_frame, s->last_frame);
203 if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
204 return ret;
205
206 *got_frame = 1;
207
208 return buf_size;
209 }
210
211 static av_cold int cmv_decode_end(AVCodecContext *avctx){
212 CmvContext *s = avctx->priv_data;
213
214 av_frame_free(&s->last_frame);
215 av_frame_free(&s->last2_frame);
216
217 return 0;
218 }
219
220 AVCodec ff_eacmv_decoder = {
221 .name = "eacmv",
222 .type = AVMEDIA_TYPE_VIDEO,
223 .id = AV_CODEC_ID_CMV,
224 .priv_data_size = sizeof(CmvContext),
225 .init = cmv_decode_init,
226 .close = cmv_decode_end,
227 .decode = cmv_decode_frame,
228 .capabilities = CODEC_CAP_DR1,
229 .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts CMV video"),
230 };