FFmpeg  4.0
eacmv.c
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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 {
39  AVFrame *last_frame; ///< last
40  AVFrame *last2_frame; ///< second-last
41  int width, height;
42  unsigned int palette[AVPALETTE_COUNT];
43 } CmvContext;
44 
46  CmvContext *s = avctx->priv_data;
47 
48  s->avctx = avctx;
49  avctx->pix_fmt = AV_PIX_FMT_PAL8;
50 
53  if (!s->last_frame || !s->last2_frame) {
56  return AVERROR(ENOMEM);
57  }
58 
59  return 0;
60 }
61 
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 
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) {
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 
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 
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 
228  CmvContext *s = avctx->priv_data;
229 
232 
233  return 0;
234 }
235 
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),
243  .close = cmv_decode_end,
245  .capabilities = AV_CODEC_CAP_DR1,
246 };
#define MVIh_TAG
Definition: eacmv.c:172
int width
Definition: eacmv.c:41
AVRational framerate
Definition: avcodec.h:3040
const char * s
Definition: avisynth_c.h:768
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int size
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
misc image utilities
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
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:104
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1431
#define AV_RB24
Definition: intreadwrite.h:64
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1727
#define AV_RL16
Definition: intreadwrite.h:42
void av_frame_move_ref(AVFrame *dst, AVFrame *src)
Move everything contained in src to dst and reset src.
Definition: frame.c:580
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3408
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
unsigned int palette[AVPALETTE_COUNT]
Definition: eacmv.c:42
uint8_t
#define av_cold
Definition: attributes.h:82
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:189
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:73
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
static int cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:133
#define AV_RB32
Definition: intreadwrite.h:130
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:441
static AVFrame * frame
const char data[16]
Definition: mxf.c:90
uint8_t * data
Definition: avcodec.h:1430
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#define AVERROR(e)
Definition: error.h:43
static void cmv_motcomp(unsigned char *dst, ptrdiff_t dst_stride, const unsigned char *src, ptrdiff_t src_stride, int x, int y, int xoffset, int yoffset, int width, int height)
Definition: eacmv.c:75
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
AVCodec ff_eacmv_decoder
Definition: eacmv.c:236
const char * name
Name of the codec implementation.
Definition: avcodec.h:3415
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:94
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:282
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:301
static int cmv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eacmv.c:174
int width
picture width / height.
Definition: avcodec.h:1690
AVFrame * last_frame
last
Definition: eacmv.c:39
#define AV_RL32
Definition: intreadwrite.h:146
if(ret< 0)
Definition: vf_mcdeint.c:279
AVCodecContext * avctx
Definition: eacmv.c:38
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:249
main external API structure.
Definition: avcodec.h:1518
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1891
void * buf
Definition: avisynth_c.h:690
Rational number (pair of numerator and denominator).
Definition: rational.h:58
static void cmv_decode_intra(CmvContext *s, AVFrame *frame, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:62
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:551
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:232
AVFrame * last2_frame
second-last
Definition: eacmv.c:40
common internal api header.
common internal and external API header
void * priv_data
Definition: avcodec.h:1545
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:296
This structure stores compressed data.
Definition: avcodec.h:1407
static av_cold int cmv_decode_end(AVCodecContext *avctx)
Definition: eacmv.c:227
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1135
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:959
#define EA_PREAMBLE_SIZE
Definition: eacmv.c:171
Predicted.
Definition: avutil.h:275