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 
51  s->last_frame = av_frame_alloc();
52  s->last2_frame = av_frame_alloc();
53  if (!s->last_frame || !s->last2_frame)
54  return AVERROR(ENOMEM);
55 
56  return 0;
57 }
58 
60  const uint8_t *buf, const uint8_t *buf_end)
61 {
62  unsigned char *dst = frame->data[0];
63  int i;
64 
65  for (i=0; i < s->avctx->height && buf_end - buf >= s->avctx->width; i++) {
66  memcpy(dst, buf, s->avctx->width);
67  dst += frame->linesize[0];
68  buf += s->avctx->width;
69  }
70 }
71 
72 static void cmv_motcomp(unsigned char *dst, ptrdiff_t dst_stride,
73  const unsigned char *src, ptrdiff_t src_stride,
74  int x, int y,
75  int xoffset, int yoffset,
76  int width, int height){
77  int i,j;
78 
79  for(j=y;j<y+4;j++)
80  for(i=x;i<x+4;i++)
81  {
82  if (i+xoffset>=0 && i+xoffset<width &&
83  j+yoffset>=0 && j+yoffset<height) {
84  dst[j*dst_stride + i] = src[(j+yoffset)*src_stride + i+xoffset];
85  }else{
86  dst[j*dst_stride + i] = 0;
87  }
88  }
89 }
90 
91 static void cmv_decode_inter(CmvContext *s, AVFrame *frame, const uint8_t *buf,
92  const uint8_t *buf_end)
93 {
94  const uint8_t *raw = buf + (s->avctx->width*s->avctx->height/16);
95  int x,y,i;
96 
97  i = 0;
98  for(y=0; y<s->avctx->height/4; y++)
99  for(x=0; x<s->avctx->width/4 && buf_end - buf > i; x++) {
100  if (buf[i]==0xFF) {
101  unsigned char *dst = frame->data[0] + (y*4)*frame->linesize[0] + x*4;
102  if (raw+16<buf_end && *raw==0xFF) { /* intra */
103  raw++;
104  memcpy(dst, raw, 4);
105  memcpy(dst + frame->linesize[0], raw+4, 4);
106  memcpy(dst + 2 * frame->linesize[0], raw+8, 4);
107  memcpy(dst + 3 * frame->linesize[0], raw+12, 4);
108  raw+=16;
109  }else if(raw<buf_end) { /* inter using second-last frame as reference */
110  int xoffset = (*raw & 0xF) - 7;
111  int yoffset = ((*raw >> 4)) - 7;
112  if (s->last2_frame->data[0])
113  cmv_motcomp(frame->data[0], frame->linesize[0],
114  s->last2_frame->data[0], s->last2_frame->linesize[0],
115  x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height);
116  raw++;
117  }
118  }else{ /* inter using last frame as reference */
119  int xoffset = (buf[i] & 0xF) - 7;
120  int yoffset = ((buf[i] >> 4)) - 7;
121  if (s->last_frame->data[0])
122  cmv_motcomp(frame->data[0], frame->linesize[0],
123  s->last_frame->data[0], s->last_frame->linesize[0],
124  x*4, y*4, xoffset, yoffset, s->avctx->width, s->avctx->height);
125  }
126  i++;
127  }
128 }
129 
130 static int cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end)
131 {
132  int pal_start, pal_count, i, ret, fps;
133 
134  if(buf_end - buf < 16) {
135  av_log(s->avctx, AV_LOG_WARNING, "truncated header\n");
136  return AVERROR_INVALIDDATA;
137  }
138 
139  s->width = AV_RL16(&buf[4]);
140  s->height = AV_RL16(&buf[6]);
141 
142  if (s->width != s->avctx->width ||
143  s->height != s->avctx->height) {
144  av_frame_unref(s->last_frame);
145  av_frame_unref(s->last2_frame);
146  }
147 
148  ret = ff_set_dimensions(s->avctx, s->width, s->height);
149  if (ret < 0)
150  return ret;
151 
152  fps = AV_RL16(&buf[10]);
153  if (fps > 0)
154  s->avctx->framerate = (AVRational){ fps, 1 };
155 
156  pal_start = AV_RL16(&buf[12]);
157  pal_count = AV_RL16(&buf[14]);
158 
159  buf += 16;
160  for (i=pal_start; i<pal_start+pal_count && i<AVPALETTE_COUNT && buf_end - buf >= 3; i++) {
161  s->palette[i] = 0xFFU << 24 | AV_RB24(buf);
162  buf += 3;
163  }
164 
165  return 0;
166 }
167 
168 #define EA_PREAMBLE_SIZE 8
169 #define MVIh_TAG MKTAG('M', 'V', 'I', 'h')
170 
172  void *data, int *got_frame,
173  AVPacket *avpkt)
174 {
175  const uint8_t *buf = avpkt->data;
176  int buf_size = avpkt->size;
177  CmvContext *s = avctx->priv_data;
178  const uint8_t *buf_end = buf + buf_size;
179  AVFrame *frame = data;
180  int ret;
181 
182  if (buf_end - buf < EA_PREAMBLE_SIZE)
183  return AVERROR_INVALIDDATA;
184 
185  if (AV_RL32(buf)==MVIh_TAG||AV_RB32(buf)==MVIh_TAG) {
186  unsigned size = AV_RL32(buf + 4);
187  ret = cmv_process_header(s, buf+EA_PREAMBLE_SIZE, buf_end);
188  if (ret < 0)
189  return ret;
190  if (size > buf_end - buf - EA_PREAMBLE_SIZE)
191  return AVERROR_INVALIDDATA;
192  buf += size;
193  }
194 
195  if ((ret = av_image_check_size(s->width, s->height, 0, s->avctx)) < 0)
196  return ret;
197 
198  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
199  return ret;
200 
201  memcpy(frame->data[1], s->palette, AVPALETTE_SIZE);
202 
203  buf += EA_PREAMBLE_SIZE;
204  if ((buf[0]&1)) { // subtype
205  cmv_decode_inter(s, frame, buf+2, buf_end);
206  frame->key_frame = 0;
207  frame->pict_type = AV_PICTURE_TYPE_P;
208  }else{
209  frame->key_frame = 1;
210  frame->pict_type = AV_PICTURE_TYPE_I;
211  cmv_decode_intra(s, frame, buf+2, buf_end);
212  }
213 
214  av_frame_unref(s->last2_frame);
215  av_frame_move_ref(s->last2_frame, s->last_frame);
216  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
217  return ret;
218 
219  *got_frame = 1;
220 
221  return buf_size;
222 }
223 
225  CmvContext *s = avctx->priv_data;
226 
227  av_frame_free(&s->last_frame);
228  av_frame_free(&s->last2_frame);
229 
230  return 0;
231 }
232 
234  .name = "eacmv",
235  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts CMV video"),
236  .type = AVMEDIA_TYPE_VIDEO,
237  .id = AV_CODEC_ID_CMV,
238  .priv_data_size = sizeof(CmvContext),
240  .close = cmv_decode_end,
242  .capabilities = AV_CODEC_CAP_DR1,
244 };
AVCodec
AVCodec.
Definition: codec.h:202
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:186
FF_CODEC_CAP_INIT_THREADSAFE
#define FF_CODEC_CAP_INIT_THREADSAFE
The codec does not modify any global variables in the init function, allowing to call the init functi...
Definition: internal.h:42
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
AVERROR
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
MVIh_TAG
#define MVIh_TAG
Definition: eacmv.c:169
cmv_decode_init
static av_cold int cmv_decode_init(AVCodecContext *avctx)
Definition: eacmv.c:45
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:112
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
data
const char data[16]
Definition: mxf.c:143
cmv_decode_end
static av_cold int cmv_decode_end(AVCodecContext *avctx)
Definition: eacmv.c:224
CmvContext::width
int width
Definition: eacmv.c:41
U
#define U(x)
Definition: vp56_arith.h:37
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:99
av_cold
#define av_cold
Definition: attributes.h:90
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
width
#define width
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AV_GET_BUFFER_FLAG_REF
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:361
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
if
if(ret)
Definition: filter_design.txt:179
CmvContext::height
int height
Definition: eacmv.c:41
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
src
#define src
Definition: vp8dsp.c:255
cmv_process_header
static int cmv_process_header(CmvContext *s, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:130
AVPALETTE_COUNT
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
CmvContext::avctx
AVCodecContext * avctx
Definition: eacmv.c:38
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1652
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
av_frame_ref
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:327
CmvContext::last_frame
AVFrame * last_frame
last
Definition: eacmv.c:39
CmvContext::palette
unsigned int palette[AVPALETTE_COUNT]
Definition: eacmv.c:42
size
int size
Definition: twinvq_data.h:10344
AV_RB32
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:96
cmv_decode_inter
static void cmv_decode_inter(CmvContext *s, AVFrame *frame, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:91
height
#define height
CmvContext
Definition: eacmv.c:37
cmv_motcomp
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:72
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
FF_CODEC_CAP_INIT_CLEANUP
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:50
common.h
av_frame_move_ref
void av_frame_move_ref(AVFrame *dst, AVFrame *src)
Move everything contained in src to dst and reset src.
Definition: frame.c:461
av_frame_unref
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:437
AV_CODEC_ID_CMV
@ AV_CODEC_ID_CMV
Definition: codec_id.h:168
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:593
avcodec.h
cmv_decode_intra
static void cmv_decode_intra(CmvContext *s, AVFrame *frame, const uint8_t *buf, const uint8_t *buf_end)
Definition: eacmv.c:59
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ret
ret
Definition: filter_design.txt:187
frame
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
Definition: filter_design.txt:264
cmv_decode_frame
static int cmv_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eacmv.c:171
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
AVCodecContext
main external API structure.
Definition: avcodec.h:383
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ff_set_dimensions
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:86
AVPacket
This structure stores compressed data.
Definition: packet.h:350
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:410
imgutils.h
CmvContext::last2_frame
AVFrame * last2_frame
second-last
Definition: eacmv.c:40
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
av_image_check_size
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:318
ff_eacmv_decoder
const AVCodec ff_eacmv_decoder
Definition: eacmv.c:233
AV_RB24
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:97
EA_PREAMBLE_SIZE
#define EA_PREAMBLE_SIZE
Definition: eacmv.c:168