FFmpeg
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 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 Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * American Laser Games MM Video Decoder
25  * by Peter Ross (pross@xvid.org)
26  *
27  * The MM format was used by IBM-PC ports of ALG's "arcade shooter" games,
28  * including Mad Dog McCree and Crime Patrol.
29  *
30  * Technical details here:
31  * http://wiki.multimedia.cx/index.php?title=American_Laser_Games_MM
32  */
33 
34 #include "libavutil/intreadwrite.h"
35 #include "avcodec.h"
36 #include "bytestream.h"
37 #include "codec_internal.h"
38 #include "internal.h"
39 
40 #define MM_PREAMBLE_SIZE 6
41 
42 #define MM_TYPE_INTER 0x5
43 #define MM_TYPE_INTRA 0x8
44 #define MM_TYPE_INTRA_HH 0xc
45 #define MM_TYPE_INTER_HH 0xd
46 #define MM_TYPE_INTRA_HHV 0xe
47 #define MM_TYPE_INTER_HHV 0xf
48 #define MM_TYPE_PALETTE 0x31
49 
50 typedef struct MmContext {
53  unsigned int palette[AVPALETTE_COUNT];
55 } MmContext;
56 
58 {
59  MmContext *s = avctx->priv_data;
60 
61  s->avctx = avctx;
62 
63  avctx->pix_fmt = AV_PIX_FMT_PAL8;
64 
65  if (!avctx->width || !avctx->height ||
66  (avctx->width & 1) || (avctx->height & 1)) {
67  av_log(avctx, AV_LOG_ERROR, "Invalid video dimensions: %dx%d\n",
68  avctx->width, avctx->height);
69  return AVERROR(EINVAL);
70  }
71 
72  s->frame = av_frame_alloc();
73  if (!s->frame)
74  return AVERROR(ENOMEM);
75 
76  return 0;
77 }
78 
79 static void mm_decode_pal(MmContext *s)
80 {
81  int i;
82 
83  bytestream2_skip(&s->gb, 4);
84  for (i = 0; i < 128; i++) {
85  s->palette[i] = 0xFFU << 24 | bytestream2_get_be24(&s->gb);
86  s->palette[i+128] = s->palette[i]<<2;
87  }
88 }
89 
90 /**
91  * @param half_horiz Half horizontal resolution (0 or 1)
92  * @param half_vert Half vertical resolution (0 or 1)
93  */
94 static int mm_decode_intra(MmContext * s, int half_horiz, int half_vert)
95 {
96  int x = 0, y = 0;
97 
98  while (bytestream2_get_bytes_left(&s->gb) > 0) {
99  int run_length, color;
100 
101  if (y >= s->avctx->height)
102  return 0;
103 
104  color = bytestream2_get_byte(&s->gb);
105  if (color & 0x80) {
106  run_length = 1;
107  }else{
108  run_length = (color & 0x7f) + 2;
109  color = bytestream2_get_byte(&s->gb);
110  }
111 
112  if (half_horiz)
113  run_length *=2;
114 
115  if (run_length > s->avctx->width - x)
116  return AVERROR_INVALIDDATA;
117 
118  if (color) {
119  memset(s->frame->data[0] + y*s->frame->linesize[0] + x, color, run_length);
120  if (half_vert && y + half_vert < s->avctx->height)
121  memset(s->frame->data[0] + (y+1)*s->frame->linesize[0] + x, color, run_length);
122  }
123  x+= run_length;
124 
125  if (x >= s->avctx->width) {
126  x=0;
127  y += 1 + half_vert;
128  }
129  }
130 
131  return 0;
132 }
133 
134 /**
135  * @param half_horiz Half horizontal resolution (0 or 1)
136  * @param half_vert Half vertical resolution (0 or 1)
137  */
138 static int mm_decode_inter(MmContext * s, int half_horiz, int half_vert)
139 {
140  int data_off = bytestream2_get_le16(&s->gb);
141  int y = 0;
142  GetByteContext data_ptr;
143 
144  if (bytestream2_get_bytes_left(&s->gb) < data_off)
145  return AVERROR_INVALIDDATA;
146 
147  bytestream2_init(&data_ptr, s->gb.buffer + data_off, bytestream2_get_bytes_left(&s->gb) - data_off);
148  while (s->gb.buffer < data_ptr.buffer_start) {
149  int i, j;
150  int length = bytestream2_get_byte(&s->gb);
151  int x = bytestream2_get_byte(&s->gb) + ((length & 0x80) << 1);
152  length &= 0x7F;
153 
154  if (length==0) {
155  y += x;
156  continue;
157  }
158 
159  if (y + half_vert >= s->avctx->height)
160  return 0;
161 
162  for(i=0; i<length; i++) {
163  int replace_array = bytestream2_get_byte(&s->gb);
164  for(j=0; j<8; j++) {
165  int replace = (replace_array >> (7-j)) & 1;
166  if (x + half_horiz >= s->avctx->width)
167  return AVERROR_INVALIDDATA;
168  if (replace) {
169  int color = bytestream2_get_byte(&data_ptr);
170  s->frame->data[0][y*s->frame->linesize[0] + x] = color;
171  if (half_horiz)
172  s->frame->data[0][y*s->frame->linesize[0] + x + 1] = color;
173  if (half_vert) {
174  s->frame->data[0][(y+1)*s->frame->linesize[0] + x] = color;
175  if (half_horiz)
176  s->frame->data[0][(y+1)*s->frame->linesize[0] + x + 1] = color;
177  }
178  }
179  x += 1 + half_horiz;
180  }
181  }
182 
183  y += 1 + half_vert;
184  }
185 
186  return 0;
187 }
188 
189 static int mm_decode_frame(AVCodecContext *avctx, AVFrame *rframe,
190  int *got_frame, AVPacket *avpkt)
191 {
192  const uint8_t *buf = avpkt->data;
193  int buf_size = avpkt->size;
194  MmContext *s = avctx->priv_data;
195  int type, res;
196 
197  if (buf_size < MM_PREAMBLE_SIZE)
198  return AVERROR_INVALIDDATA;
199  type = AV_RL16(&buf[0]);
200  buf += MM_PREAMBLE_SIZE;
201  buf_size -= MM_PREAMBLE_SIZE;
202  bytestream2_init(&s->gb, buf, buf_size);
203 
204  if ((res = ff_reget_buffer(avctx, s->frame, 0)) < 0)
205  return res;
206 
207  switch(type) {
208  case MM_TYPE_PALETTE : mm_decode_pal(s); return avpkt->size;
209  case MM_TYPE_INTRA : res = mm_decode_intra(s, 0, 0); break;
210  case MM_TYPE_INTRA_HH : res = mm_decode_intra(s, 1, 0); break;
211  case MM_TYPE_INTRA_HHV : res = mm_decode_intra(s, 1, 1); break;
212  case MM_TYPE_INTER : res = mm_decode_inter(s, 0, 0); break;
213  case MM_TYPE_INTER_HH : res = mm_decode_inter(s, 1, 0); break;
214  case MM_TYPE_INTER_HHV : res = mm_decode_inter(s, 1, 1); break;
215  default:
216  res = AVERROR_INVALIDDATA;
217  break;
218  }
219  if (res < 0)
220  return res;
221 
222  memcpy(s->frame->data[1], s->palette, AVPALETTE_SIZE);
223 
224  if ((res = av_frame_ref(rframe, s->frame)) < 0)
225  return res;
226 
227  *got_frame = 1;
228 
229  return avpkt->size;
230 }
231 
233 {
234  MmContext *s = avctx->priv_data;
235 
236  av_frame_free(&s->frame);
237 
238  return 0;
239 }
240 
242  .p.name = "mmvideo",
243  .p.long_name = NULL_IF_CONFIG_SMALL("American Laser Games MM Video"),
244  .p.type = AVMEDIA_TYPE_VIDEO,
245  .p.id = AV_CODEC_ID_MMVIDEO,
246  .priv_data_size = sizeof(MmContext),
247  .init = mm_decode_init,
248  .close = mm_decode_end,
250  .p.capabilities = AV_CODEC_CAP_DR1,
251  .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
252 };
ff_mmvideo_decoder
const FFCodec ff_mmvideo_decoder
Definition: mmvideo.c:241
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
GetByteContext::buffer_start
const uint8_t * buffer_start
Definition: bytestream.h:34
color
Definition: vf_paletteuse.c:600
GetByteContext
Definition: bytestream.h:33
av_frame_free
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:111
MM_TYPE_INTER_HH
#define MM_TYPE_INTER_HH
Definition: mmvideo.c:45
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
FFCodec
Definition: codec_internal.h:112
MmContext::gb
GetByteContext gb
Definition: mmvideo.c:54
init
static int init
Definition: av_tx.c:47
mm_decode_intra
static int mm_decode_intra(MmContext *s, int half_horiz, int half_vert)
Definition: mmvideo.c:94
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:116
U
#define U(x)
Definition: vp56_arith.h:37
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
MmContext::avctx
AVCodecContext * avctx
Definition: mmvideo.c:51
mm_decode_end
static av_cold int mm_decode_end(AVCodecContext *avctx)
Definition: mmvideo.c:232
av_frame_alloc
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:99
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:254
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
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
MmContext::palette
unsigned int palette[AVPALETTE_COUNT]
Definition: mmvideo.c:53
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
MM_TYPE_PALETTE
#define MM_TYPE_PALETTE
Definition: mmvideo.c:48
AVPALETTE_COUNT
#define AVPALETTE_COUNT
Definition: pixfmt.h:33
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
MM_PREAMBLE_SIZE
#define MM_PREAMBLE_SIZE
Definition: mmvideo.c:40
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:375
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:116
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:343
codec_internal.h
color
static const uint32_t color[16+AV_CLASS_CATEGORY_NB]
Definition: log.c:94
MM_TYPE_INTER_HHV
#define MM_TYPE_INTER_HHV
Definition: mmvideo.c:47
MM_TYPE_INTER
#define MM_TYPE_INTER
Definition: mmvideo.c:42
AV_CODEC_ID_MMVIDEO
@ AV_CODEC_ID_MMVIDEO
Definition: codec_id.h:130
MM_TYPE_INTRA_HH
#define MM_TYPE_INTRA_HH
Definition: mmvideo.c:44
mm_decode_inter
static int mm_decode_inter(MmContext *s, int half_horiz, int half_vert)
Definition: mmvideo.c:138
MM_TYPE_INTRA
#define MM_TYPE_INTRA
Definition: mmvideo.c:43
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
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: codec_internal.h:31
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:203
AVCodecContext::height
int height
Definition: avcodec.h:562
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:599
MM_TYPE_INTRA_HHV
#define MM_TYPE_INTRA_HHV
Definition: mmvideo.c:46
mm_decode_frame
static int mm_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame, AVPacket *avpkt)
Definition: mmvideo.c:189
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ff_reget_buffer
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available.
Definition: decode.c:1521
half_vert
static uint8_t half_vert(BlockXY bxy)
Definition: mobiclip.c:575
AVCodecContext
main external API structure.
Definition: avcodec.h:389
MmContext
Definition: mmvideo.c:50
mm_decode_pal
static void mm_decode_pal(MmContext *s)
Definition: mmvideo.c:79
mm_decode_init
static av_cold int mm_decode_init(AVCodecContext *avctx)
Definition: mmvideo.c:57
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
MmContext::frame
AVFrame * frame
Definition: mmvideo.c:52
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:416
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:562
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61