FFmpeg
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 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 AVERROR_INVALIDDATA;
195  buf += size;
196  }
197 
198  if ((ret = av_image_check_size(s->width, s->height, 0, s->avctx)) < 0)
199  return ret;
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:3101
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
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:1478
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
void av_frame_move_ref(AVFrame *dst, AVFrame *src)
Move everything contained in src to dst and reset src.
Definition: frame.c:582
#define src
Definition: vp8dsp.c:254
AVCodec.
Definition: avcodec.h:3477
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
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:77
#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
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:443
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:87
uint8_t * data
Definition: avcodec.h:1477
ptrdiff_t size
Definition: opengl_enc.c:100
#define av_log(a,...)
#define U(x)
Definition: vp56_arith.h:37
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:260
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:3484
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:351
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:1738
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
AVFrame * last_frame
last
Definition: eacmv.c:39
#define s(width, name)
Definition: cbs_vp9.c:257
if(ret)
AVCodecContext * avctx
Definition: eacmv.c:38
Libavcodec external API header.
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_RB24
Definition: bytestream.h:87
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:299
main external API structure.
Definition: avcodec.h:1565
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
void * buf
Definition: avisynth_c.h:766
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:553
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
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:1592
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:346
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1454
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:1176
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981
#define EA_PREAMBLE_SIZE
Definition: eacmv.c:171
Predicted.
Definition: avutil.h:275