Libav
mmvideo.c
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1 /*
2  * American Laser Games MM Video Decoder
3  * Copyright (c) 2006,2008 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 Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
34 #include "libavutil/intreadwrite.h"
35 #include "avcodec.h"
36 #include "bytestream.h"
37 #include "internal.h"
38 
39 #define MM_PREAMBLE_SIZE 6
40 
41 #define MM_TYPE_INTER 0x5
42 #define MM_TYPE_INTRA 0x8
43 #define MM_TYPE_INTRA_HH 0xc
44 #define MM_TYPE_INTER_HH 0xd
45 #define MM_TYPE_INTRA_HHV 0xe
46 #define MM_TYPE_INTER_HHV 0xf
47 #define MM_TYPE_PALETTE 0x31
48 
49 typedef struct MmContext {
54 } MmContext;
55 
57 {
58  MmContext *s = avctx->priv_data;
59 
60  s->avctx = avctx;
61 
62  avctx->pix_fmt = AV_PIX_FMT_PAL8;
63 
64  if (!avctx->width || !avctx->height ||
65  (avctx->width & 1) || (avctx->height & 1)) {
66  av_log(avctx, AV_LOG_ERROR, "Invalid video dimensions: %dx%d\n",
67  avctx->width, avctx->height);
68  return AVERROR(EINVAL);
69  }
70 
71  s->frame = av_frame_alloc();
72  if (!s->frame)
73  return AVERROR(ENOMEM);
74 
75  return 0;
76 }
77 
78 static int mm_decode_pal(MmContext *s)
79 {
80  int i;
81 
82  bytestream2_skip(&s->gb, 4);
83  for (i = 0; i < 128; i++) {
84  s->palette[i] = bytestream2_get_be24(&s->gb);
85  s->palette[i+128] = s->palette[i]<<2;
86  }
87 
88  return 0;
89 }
90 
95 static int mm_decode_intra(MmContext * s, int half_horiz, int half_vert)
96 {
97  int x = 0, y = 0;
98 
99  while (bytestream2_get_bytes_left(&s->gb) > 0) {
100  int run_length, color;
101 
102  // writes one more line when half_vert is true
103  if (y >= s->avctx->height + !!half_vert)
104  return 0;
105 
106  color = bytestream2_get_byte(&s->gb);
107  if (color & 0x80) {
108  run_length = 1;
109  }else{
110  run_length = (color & 0x7f) + 2;
111  color = bytestream2_get_byte(&s->gb);
112  }
113 
114  if (half_horiz)
115  run_length *=2;
116 
117  if (s->avctx->width - x < run_length)
118  return AVERROR_INVALIDDATA;
119 
120  if (color) {
121  memset(s->frame->data[0] + y*s->frame->linesize[0] + x, color, run_length);
122  if (half_vert)
123  memset(s->frame->data[0] + (y+1)*s->frame->linesize[0] + x, color, run_length);
124  }
125  x+= run_length;
126 
127  if (x >= s->avctx->width) {
128  x=0;
129  y += 1 + half_vert;
130  }
131  }
132 
133  return 0;
134 }
135 
136 /*
137  * @param half_horiz Half horizontal resolution (0 or 1)
138  * @param half_vert Half vertical resolution (0 or 1)
139  */
140 static int mm_decode_inter(MmContext * s, int half_horiz, int half_vert)
141 {
142  int data_off = bytestream2_get_le16(&s->gb);
143  int y = 0;
144  GetByteContext data_ptr;
145 
146  if (bytestream2_get_bytes_left(&s->gb) < data_off)
147  return AVERROR_INVALIDDATA;
148 
149  bytestream2_init(&data_ptr, s->gb.buffer + data_off, bytestream2_get_bytes_left(&s->gb) - data_off);
150  while (s->gb.buffer < data_ptr.buffer_start) {
151  int i, j;
152  int length = bytestream2_get_byte(&s->gb);
153  int x = bytestream2_get_byte(&s->gb) + ((length & 0x80) << 1);
154  length &= 0x7F;
155 
156  if (length==0) {
157  y += x;
158  continue;
159  }
160 
161  if (y + half_vert >= s->avctx->height)
162  return 0;
163 
164  for(i=0; i<length; i++) {
165  int replace_array = bytestream2_get_byte(&s->gb);
166  for(j=0; j<8; j++) {
167  int replace = (replace_array >> (7-j)) & 1;
168  if (x + half_horiz >= s->avctx->width)
169  return AVERROR_INVALIDDATA;
170  if (replace) {
171  int color = bytestream2_get_byte(&data_ptr);
172  s->frame->data[0][y*s->frame->linesize[0] + x] = color;
173  if (half_horiz)
174  s->frame->data[0][y*s->frame->linesize[0] + x + 1] = color;
175  if (half_vert) {
176  s->frame->data[0][(y+1)*s->frame->linesize[0] + x] = color;
177  if (half_horiz)
178  s->frame->data[0][(y+1)*s->frame->linesize[0] + x + 1] = color;
179  }
180  }
181  x += 1 + half_horiz;
182  }
183  }
184 
185  y += 1 + half_vert;
186  }
187 
188  return 0;
189 }
190 
192  void *data, int *got_frame,
193  AVPacket *avpkt)
194 {
195  const uint8_t *buf = avpkt->data;
196  int buf_size = avpkt->size;
197  MmContext *s = avctx->priv_data;
198  int type, res;
199 
200  if (buf_size < MM_PREAMBLE_SIZE)
201  return AVERROR_INVALIDDATA;
202  type = AV_RL16(&buf[0]);
203  buf += MM_PREAMBLE_SIZE;
204  buf_size -= MM_PREAMBLE_SIZE;
205  bytestream2_init(&s->gb, buf, buf_size);
206 
207  if ((res = ff_reget_buffer(avctx, s->frame)) < 0) {
208  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
209  return res;
210  }
211 
212  switch(type) {
213  case MM_TYPE_PALETTE : res = mm_decode_pal(s); return buf_size;
214  case MM_TYPE_INTRA : res = mm_decode_intra(s, 0, 0); break;
215  case MM_TYPE_INTRA_HH : res = mm_decode_intra(s, 1, 0); break;
216  case MM_TYPE_INTRA_HHV : res = mm_decode_intra(s, 1, 1); break;
217  case MM_TYPE_INTER : res = mm_decode_inter(s, 0, 0); break;
218  case MM_TYPE_INTER_HH : res = mm_decode_inter(s, 1, 0); break;
219  case MM_TYPE_INTER_HHV : res = mm_decode_inter(s, 1, 1); break;
220  default:
221  res = AVERROR_INVALIDDATA;
222  break;
223  }
224  if (res < 0)
225  return res;
226 
227  memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);
228 
229  if ((res = av_frame_ref(data, s->frame)) < 0)
230  return res;
231 
232  *got_frame = 1;
233 
234  return buf_size;
235 }
236 
238 {
239  MmContext *s = avctx->priv_data;
240 
241  av_frame_free(&s->frame);
242 
243  return 0;
244 }
245 
247  .name = "mmvideo",
248  .long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"),
249  .type = AVMEDIA_TYPE_VIDEO,
250  .id = AV_CODEC_ID_MMVIDEO,
251  .priv_data_size = sizeof(MmContext),
252  .init = mm_decode_init,
253  .close = mm_decode_end,
255  .capabilities = CODEC_CAP_DR1,
256 };
#define AVPALETTE_SIZE
Definition: avcodec.h:3051
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
static int mm_decode_pal(MmContext *s)
Definition: mmvideo.c:78
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
static int mm_decode_intra(MmContext *s, int half_horiz, int half_vert)
Definition: mmvideo.c:95
int size
Definition: avcodec.h:974
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1270
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:132
#define AV_RL16
Definition: intreadwrite.h:42
#define AVPALETTE_COUNT
Definition: avcodec.h:3052
#define MM_TYPE_INTER_HH
Definition: mmvideo.c:44
AVCodec.
Definition: avcodec.h:2812
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
uint8_t
#define av_cold
Definition: attributes.h:66
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
static int mm_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mmvideo.c:191
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
#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
uint8_t * data
Definition: avcodec.h:973
const uint8_t * buffer
Definition: bytestream.h:33
int palette[AVPALETTE_COUNT]
Definition: mmvideo.c:52
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:161
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:145
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:151
static av_cold int mm_decode_end(AVCodecContext *avctx)
Definition: mmvideo.c:237
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
const char * name
Name of the codec implementation.
Definition: avcodec.h:2819
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame)
Identical in function to av_frame_make_writable(), except it uses ff_get_buffer() to allocate the buf...
Definition: utils.c:808
#define MM_PREAMBLE_SIZE
Definition: mmvideo.c:39
int width
picture width / height.
Definition: avcodec.h:1229
#define MM_TYPE_INTER
Definition: mmvideo.c:41
AVFrame * frame
Definition: mmvideo.c:51
#define MM_TYPE_INTRA_HHV
Definition: mmvideo.c:45
#define MM_TYPE_PALETTE
Definition: mmvideo.c:47
AVCodec ff_mmvideo_decoder
Definition: mmvideo.c:246
if(ac->has_optimized_func)
static int mm_decode_inter(MmContext *s, int half_horiz, int half_vert)
Definition: mmvideo.c:140
#define MM_TYPE_INTRA_HH
Definition: mmvideo.c:43
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:153
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
static av_cold int mm_decode_init(AVCodecContext *avctx)
Definition: mmvideo.c:56
const uint8_t * buffer_start
Definition: bytestream.h:33
#define MM_TYPE_INTRA
Definition: mmvideo.c:42
#define MM_TYPE_INTER_HHV
Definition: mmvideo.c:46
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
common internal api header.
GetByteContext gb
Definition: mmvideo.c:53
AVCodecContext * avctx
Definition: mmvideo.c:50
static const uint8_t color[]
Definition: log.c:55
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
void * priv_data
Definition: avcodec.h:1092
This structure stores compressed data.
Definition: avcodec.h:950