Libav
eacmv.c
Go to the documentation of this file.
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 
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 {
41  int width, height;
42  unsigned int palette[AVPALETTE_COUNT];
43 } CmvContext;
44 
46  CmvContext *s = avctx->priv_data;
47  s->avctx = avctx;
48  avctx->pix_fmt = AV_PIX_FMT_PAL8;
49 
52  if (!s->last_frame || !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  if (s->last_frame->data[0])
124  cmv_motcomp(frame->data[0], frame->linesize[0],
125  s->last_frame->data[0], s->last_frame->linesize[0],
126  x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height);
127  }
128  i++;
129  }
130 }
131 
132 static int cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end)
133 {
134  int pal_start, pal_count, i, ret, fps;
135 
136  if(buf_end - buf < 16) {
137  av_log(s->avctx, AV_LOG_WARNING, "truncated header\n");
138  return AVERROR_INVALIDDATA;
139  }
140 
141  s->width = AV_RL16(&buf[4]);
142  s->height = AV_RL16(&buf[6]);
143 
144  if (s->width != s->avctx->width ||
145  s->height != s->avctx->height) {
148  }
149 
150  ret = ff_set_dimensions(s->avctx, s->width, s->height);
151  if (ret < 0)
152  return ret;
153 
154  fps = AV_RL16(&buf[10]);
155  if (fps > 0)
156  s->avctx->time_base = (AVRational){ 1, fps };
157 
158  pal_start = AV_RL16(&buf[12]);
159  pal_count = AV_RL16(&buf[14]);
160 
161  buf += 16;
162  for (i=pal_start; i<pal_start+pal_count && i<AVPALETTE_COUNT && buf_end - buf >= 3; i++) {
163  s->palette[i] = AV_RB24(buf);
164  buf += 3;
165  }
166 
167  return 0;
168 }
169 
170 #define EA_PREAMBLE_SIZE 8
171 #define MVIh_TAG MKTAG('M', 'V', 'I', 'h')
172 
174  void *data, int *got_frame,
175  AVPacket *avpkt)
176 {
177  const uint8_t *buf = avpkt->data;
178  int buf_size = avpkt->size;
179  CmvContext *s = avctx->priv_data;
180  const uint8_t *buf_end = buf + buf_size;
181  AVFrame *frame = data;
182  int ret;
183 
184  if (buf_end - buf < EA_PREAMBLE_SIZE)
185  return AVERROR_INVALIDDATA;
186 
187  if (AV_RL32(buf)==MVIh_TAG||AV_RB32(buf)==MVIh_TAG) {
188  ret = cmv_process_header(s, buf+EA_PREAMBLE_SIZE, buf_end);
189  if (ret < 0)
190  return ret;
191  return buf_size;
192  }
193 
194  if (av_image_check_size(s->width, s->height, 0, s->avctx))
195  return -1;
196 
197  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
198  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
199  return ret;
200  }
201 
202  memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
203 
204  buf += EA_PREAMBLE_SIZE;
205  if ((buf[0]&1)) { // subtype
206  cmv_decode_inter(s, frame, buf+2, buf_end);
207  frame->key_frame = 0;
208  frame->pict_type = AV_PICTURE_TYPE_P;
209  }else{
210  frame->key_frame = 1;
211  frame->pict_type = AV_PICTURE_TYPE_I;
212  cmv_decode_intra(s, frame, buf+2, buf_end);
213  }
214 
217  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
218  return ret;
219 
220  *got_frame = 1;
221 
222  return buf_size;
223 }
224 
226  CmvContext *s = avctx->priv_data;
227 
230 
231  return 0;
232 }
233 
235  .name = "eacmv",
236  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts CMV video"),
237  .type = AVMEDIA_TYPE_VIDEO,
238  .id = AV_CODEC_ID_CMV,
239  .priv_data_size = sizeof(CmvContext),
243  .capabilities = CODEC_CAP_DR1,
244 };
#define AVPALETTE_SIZE
Definition: avcodec.h:3035
#define MVIh_TAG
Definition: eacmv.c:171
int width
Definition: eacmv.c:41
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:133
#define AV_RL16(x)
Definition: intreadwrite.h:220
int size
Definition: avcodec.h:974
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1254
#define AVPALETTE_COUNT
Definition: avcodec.h:3036
void av_frame_move_ref(AVFrame *dst, AVFrame *src)
Move everythnig contained in src to dst and reset src.
Definition: frame.c:300
AVCodec.
Definition: avcodec.h:2796
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1175
unsigned int palette[AVPALETTE_COUNT]
Definition: eacmv.c:42
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
uint8_t
static int cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:132
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:188
const char * name
Name of the codec implementation.
Definition: avcodec.h:2803
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:69
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
AVCodec ff_eacmv_decoder
Definition: eacmv.c:234
Libavcodec external API header.
int height
Definition: eacmv.c:41
static void cmv_decode_inter(CmvContext *s, AVFrame *frame, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:93
static av_cold int cmv_decode_init(AVCodecContext *avctx)
Definition: eacmv.c:45
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:222
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:196
static int cmv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eacmv.c:173
int width
picture width / height.
Definition: avcodec.h:1224
AVFrame * last_frame
last
Definition: eacmv.c:39
static void cmv_motcomp(unsigned char *dst, int dst_stride, const unsigned char *src, int src_stride, int x, int y, int xoffset, int yoffset, int width, int height)
Definition: eacmv.c:74
if(ac->has_optimized_func)
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
static int width
Definition: utils.c:156
AVCodecContext * avctx
Definition: eacmv.c:38
#define av_cold
Definition: attributes.h:66
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:612
rational number numerator/denominator
Definition: rational.h:43
uint8_t * data
Definition: avcodec.h:973
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:153
static void cmv_decode_intra(CmvContext *s, AVFrame *frame, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:61
#define AV_RB24(x)
Definition: intreadwrite.h:406
void * priv_data
Definition: avcodec.h:1092
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:283
int height
Definition: gxfenc.c:72
AVFrame * last2_frame
second-last
Definition: eacmv.c:40
common internal api header.
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
#define AV_RB32(x)
Definition: intreadwrite.h:232
#define AV_RL32(x)
Definition: intreadwrite.h:248
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:191
This structure stores compressed data.
Definition: avcodec.h:950
static av_cold int cmv_decode_end(AVCodecContext *avctx)
Definition: eacmv.c:225
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:850
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
#define EA_PREAMBLE_SIZE
Definition: eacmv.c:170
Predicted.
Definition: avutil.h:254