give the user a chance to override codec_tag
[libav.git] / libavcodec / raw.c
1 /*
2 * Raw Video Codec
3 * Copyright (c) 2001 Fabrice Bellard.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
14 *
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20 /**
21 * @file raw.c
22 * Raw Video Codec
23 */
24
25 #include "avcodec.h"
26
27 typedef struct RawVideoContext {
28 unsigned char * buffer; /* block of memory for holding one frame */
29 unsigned char * p; /* current position in buffer */
30 int length; /* number of bytes in buffer */
31 AVFrame pic; ///< AVCodecContext.coded_frame
32 } RawVideoContext;
33
34 typedef struct PixleFormatTag {
35 int pix_fmt;
36 unsigned int fourcc;
37 } PixelFormatTag;
38
39 const PixelFormatTag pixelFormatTags[] = {
40 { PIX_FMT_YUV420P, MKTAG('I', '4', '2', '0') }, /* Planar formats */
41 { PIX_FMT_YUV420P, MKTAG('I', 'Y', 'U', 'V') },
42 { PIX_FMT_YUV410P, MKTAG('Y', 'U', 'V', '9') },
43 { PIX_FMT_YUV411P, MKTAG('Y', '4', '1', 'B') },
44 { PIX_FMT_YUV422P, MKTAG('Y', '4', '2', 'B') },
45 { PIX_FMT_GRAY8, MKTAG('Y', '8', '0', '0') },
46 { PIX_FMT_GRAY8, MKTAG(' ', ' ', 'Y', '8') },
47
48
49 { PIX_FMT_YUV422, MKTAG('Y', '4', '2', '2') }, /* Packed formats */
50 { PIX_FMT_UYVY422, MKTAG('U', 'Y', 'V', 'Y') },
51 { PIX_FMT_GRAY8, MKTAG('G', 'R', 'E', 'Y') },
52
53 { -1, 0 },
54 };
55
56 static int findPixelFormat(unsigned int fourcc)
57 {
58 const PixelFormatTag * tags = pixelFormatTags;
59 while (tags->pix_fmt >= 0) {
60 if (tags->fourcc == fourcc)
61 return tags->pix_fmt;
62 tags++;
63 }
64 return PIX_FMT_YUV420P;
65 }
66
67 static unsigned int findFourCC(int fmt)
68 {
69 const PixelFormatTag * tags = pixelFormatTags;
70 while (tags->pix_fmt >= 0) {
71 if (tags->pix_fmt == fmt)
72 return tags->fourcc;
73 tags++;
74 }
75 return 0;
76 }
77
78 /* RAW Decoder Implementation */
79
80 static int raw_init_decoder(AVCodecContext *avctx)
81 {
82 RawVideoContext *context = avctx->priv_data;
83
84 if (avctx->codec_tag)
85 avctx->pix_fmt = findPixelFormat(avctx->codec_tag);
86 else if (avctx->bits_per_sample){
87 switch(avctx->bits_per_sample){
88 case 15: avctx->pix_fmt= PIX_FMT_RGB555; break;
89 case 16: avctx->pix_fmt= PIX_FMT_RGB565; break;
90 case 24: avctx->pix_fmt= PIX_FMT_BGR24 ; break;
91 case 32: avctx->pix_fmt= PIX_FMT_RGBA32; break;
92 }
93 }
94
95 context->length = avpicture_get_size(avctx->pix_fmt, avctx->width, avctx->height);
96 context->buffer = av_malloc(context->length);
97 context->p = context->buffer;
98 context->pic.pict_type = FF_I_TYPE;
99 context->pic.key_frame = 1;
100
101 avctx->coded_frame= &context->pic;
102
103 if (!context->buffer)
104 return -1;
105
106 return 0;
107 }
108
109 static int raw_decode(AVCodecContext *avctx,
110 void *data, int *data_size,
111 uint8_t *buf, int buf_size)
112 {
113 RawVideoContext *context = avctx->priv_data;
114 int bytesNeeded;
115
116 AVPicture * picture = (AVPicture *) data;
117
118 /* Early out without copy if packet size == frame size */
119 if (buf_size == context->length && context->p == context->buffer) {
120 avpicture_fill(picture, buf, avctx->pix_fmt, avctx->width, avctx->height);
121 *data_size = sizeof(AVPicture);
122 return buf_size;
123 }
124
125 bytesNeeded = context->length - (context->p - context->buffer);
126 if (buf_size < bytesNeeded) {
127 memcpy(context->p, buf, buf_size);
128 context->p += buf_size;
129 return buf_size;
130 }
131
132 memcpy(context->p, buf, bytesNeeded);
133 context->p = context->buffer;
134 avpicture_fill(picture, context->buffer, avctx->pix_fmt, avctx->width, avctx->height);
135 *data_size = sizeof(AVPicture);
136 return bytesNeeded;
137 }
138
139 static int raw_close_decoder(AVCodecContext *avctx)
140 {
141 RawVideoContext *context = avctx->priv_data;
142
143 av_freep(&context->buffer);
144 return 0;
145 }
146
147 /* RAW Encoder Implementation */
148
149 static int raw_init_encoder(AVCodecContext *avctx)
150 {
151 avctx->coded_frame = (AVFrame *)avctx->priv_data;
152 avctx->coded_frame->pict_type = FF_I_TYPE;
153 avctx->coded_frame->key_frame = 1;
154 if(!avctx->codec_tag)
155 avctx->codec_tag = findFourCC(avctx->pix_fmt);
156 return 0;
157 }
158
159 static int raw_encode(AVCodecContext *avctx,
160 unsigned char *frame, int buf_size, void *data)
161 {
162 return avpicture_layout((AVPicture *)data, avctx->pix_fmt, avctx->width,
163 avctx->height, frame, buf_size);
164 }
165
166 AVCodec rawvideo_encoder = {
167 "rawvideo",
168 CODEC_TYPE_VIDEO,
169 CODEC_ID_RAWVIDEO,
170 sizeof(AVFrame),
171 raw_init_encoder,
172 raw_encode,
173 };
174
175 AVCodec rawvideo_decoder = {
176 "rawvideo",
177 CODEC_TYPE_VIDEO,
178 CODEC_ID_RAWVIDEO,
179 sizeof(RawVideoContext),
180 raw_init_decoder,
181 NULL,
182 raw_close_decoder,
183 raw_decode,
184 };