FFmpeg  4.4.5
midivid.c
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1 /*
2  * MidiVid decoder
3  * Copyright (c) 2019 Paul B Mahol
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 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 
26 #include "libavutil/imgutils.h"
27 #include "libavutil/internal.h"
28 #include "libavutil/intreadwrite.h"
29 #include "libavutil/mem.h"
30 
31 #define BITSTREAM_READER_LE
32 #include "avcodec.h"
33 #include "get_bits.h"
34 #include "bytestream.h"
35 #include "internal.h"
36 
37 typedef struct MidiVidContext {
39 
41  unsigned int uncompressed_size;
43 
46 
48 {
49  GetByteContext *gb = &s->gb;
51  GetByteContext idx9;
52  uint16_t nb_vectors, intra_flag;
53  const uint8_t *vec;
54  const uint8_t *mask_start;
55  uint8_t *skip;
56  uint32_t mask_size;
57  int idx9bits = 0;
58  int idx9val = 0;
59  uint32_t nb_blocks;
60 
61  nb_vectors = bytestream2_get_le16(gb);
62  intra_flag = !!bytestream2_get_le16(gb);
63  if (intra_flag) {
64  nb_blocks = (avctx->width / 2) * (avctx->height / 2);
65  } else {
66  int ret, skip_linesize, padding;
67 
68  nb_blocks = bytestream2_get_le32(gb);
69  skip_linesize = avctx->width >> 1;
70  mask_start = gb->buffer_start + bytestream2_tell(gb);
71  mask_size = (FFALIGN(avctx->width, 32) >> 2) * (avctx->height >> 2) >> 3;
72  padding = (FFALIGN(avctx->width, 32) - avctx->width) >> 2;
73 
74  if (bytestream2_get_bytes_left(gb) < mask_size)
75  return AVERROR_INVALIDDATA;
76 
77  ret = init_get_bits8(&mask, mask_start, mask_size);
78  if (ret < 0)
79  return ret;
80  bytestream2_skip(gb, mask_size);
81  skip = s->skip;
82 
83  for (int y = 0; y < avctx->height >> 2; y++) {
84  for (int x = 0; x < avctx->width >> 2; x++) {
85  int flag = !get_bits1(&mask);
86 
87  skip[(y*2) *skip_linesize + x*2 ] = flag;
88  skip[(y*2) *skip_linesize + x*2+1] = flag;
89  skip[(y*2+1)*skip_linesize + x*2 ] = flag;
90  skip[(y*2+1)*skip_linesize + x*2+1] = flag;
91  }
92  skip_bits_long(&mask, padding);
93  }
94  }
95 
96  vec = gb->buffer_start + bytestream2_tell(gb);
97  if (bytestream2_get_bytes_left(gb) < nb_vectors * 12)
98  return AVERROR_INVALIDDATA;
99  bytestream2_skip(gb, nb_vectors * 12);
100  if (nb_vectors > 256) {
101  if (bytestream2_get_bytes_left(gb) < (nb_blocks + 7 * !intra_flag) / 8)
102  return AVERROR_INVALIDDATA;
103  bytestream2_init(&idx9, gb->buffer_start + bytestream2_tell(gb), (nb_blocks + 7 * !intra_flag) / 8);
104  bytestream2_skip(gb, (nb_blocks + 7 * !intra_flag) / 8);
105  }
106 
107  skip = s->skip;
108 
109  for (int y = avctx->height - 2; y >= 0; y -= 2) {
110  uint8_t *dsty = frame->data[0] + y * frame->linesize[0];
111  uint8_t *dstu = frame->data[1] + y * frame->linesize[1];
112  uint8_t *dstv = frame->data[2] + y * frame->linesize[2];
113 
114  for (int x = 0; x < avctx->width; x += 2) {
115  int idx;
116 
117  if (!intra_flag && *skip++)
118  continue;
119  if (bytestream2_get_bytes_left(gb) <= 0)
120  return AVERROR_INVALIDDATA;
121  if (nb_vectors <= 256) {
122  idx = bytestream2_get_byte(gb);
123  } else {
124  if (idx9bits == 0) {
125  idx9val = bytestream2_get_byte(&idx9);
126  idx9bits = 8;
127  }
128  idx9bits--;
129  idx = bytestream2_get_byte(gb) | (((idx9val >> (7 - idx9bits)) & 1) << 8);
130  }
131  if (idx >= nb_vectors)
132  return AVERROR_INVALIDDATA;
133 
134  dsty[x +frame->linesize[0]] = vec[idx * 12 + 0];
135  dsty[x+1+frame->linesize[0]] = vec[idx * 12 + 3];
136  dsty[x] = vec[idx * 12 + 6];
137  dsty[x+1] = vec[idx * 12 + 9];
138 
139  dstu[x +frame->linesize[1]] = vec[idx * 12 + 1];
140  dstu[x+1+frame->linesize[1]] = vec[idx * 12 + 4];
141  dstu[x] = vec[idx * 12 + 7];
142  dstu[x+1] = vec[idx * 12 +10];
143 
144  dstv[x +frame->linesize[2]] = vec[idx * 12 + 2];
145  dstv[x+1+frame->linesize[2]] = vec[idx * 12 + 5];
146  dstv[x] = vec[idx * 12 + 8];
147  dstv[x+1] = vec[idx * 12 +11];
148  }
149  }
150 
151  return intra_flag;
152 }
153 
154 static ptrdiff_t lzss_uncompress(MidiVidContext *s, GetByteContext *gb, uint8_t *dst, unsigned int size)
155 {
156  uint8_t *dst_start = dst;
157  uint8_t *dst_end = dst + size;
158 
159  for (;bytestream2_get_bytes_left(gb) >= 3;) {
160  int op = bytestream2_get_le16(gb);
161 
162  for (int i = 0; i < 16; i++) {
163  if (op & 1) {
164  int s0 = bytestream2_get_byte(gb);
165  int s1 = bytestream2_get_byte(gb);
166  int offset = ((s0 & 0xF0) << 4) | s1;
167  int length = (s0 & 0xF) + 3;
168 
169  if (dst + length > dst_end ||
170  dst - offset < dst_start)
171  return AVERROR_INVALIDDATA;
172  if (offset > 0) {
173  for (int j = 0; j < length; j++) {
174  dst[j] = dst[j - offset];
175  }
176  }
177  dst += length;
178  } else {
179  if (dst >= dst_end)
180  return AVERROR_INVALIDDATA;
181  *dst++ = bytestream2_get_byte(gb);
182  }
183  op >>= 1;
184  }
185  }
186 
187  return dst - dst_start;
188 }
189 
190 static int decode_frame(AVCodecContext *avctx, void *data,
191  int *got_frame, AVPacket *avpkt)
192 {
193  MidiVidContext *s = avctx->priv_data;
194  GetByteContext *gb = &s->gb;
195  AVFrame *frame = s->frame;
196  int ret, key, uncompressed;
197 
198  if (avpkt->size <= 13)
199  return AVERROR_INVALIDDATA;
200 
201  bytestream2_init(gb, avpkt->data, avpkt->size);
202  bytestream2_skip(gb, 8);
203  uncompressed = bytestream2_get_le32(gb);
204 
205  if (!uncompressed) {
206  av_fast_padded_malloc(&s->uncompressed, &s->uncompressed_size, 16LL * (avpkt->size - 12));
207  if (!s->uncompressed)
208  return AVERROR(ENOMEM);
209 
210  ret = lzss_uncompress(s, gb, s->uncompressed, s->uncompressed_size);
211  if (ret < 0)
212  return ret;
213  bytestream2_init(gb, s->uncompressed, ret);
214  }
215 
216  if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
217  return ret;
218 
219  ret = decode_mvdv(s, avctx, frame);
220 
221  if (ret < 0)
222  return ret;
223  key = ret;
224 
225  if ((ret = av_frame_ref(data, s->frame)) < 0)
226  return ret;
227 
229  frame->key_frame = key;
230  *got_frame = 1;
231 
232  return avpkt->size;
233 }
234 
236 {
237  MidiVidContext *s = avctx->priv_data;
238  int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
239 
240  if (avctx->width & 3 || avctx->height & 3)
241  ret = AVERROR_INVALIDDATA;
242 
243  if (ret < 0) {
244  av_log(avctx, AV_LOG_ERROR, "Invalid image size %dx%d.\n",
245  avctx->width, avctx->height);
246  return ret;
247  }
248 
249  avctx->pix_fmt = AV_PIX_FMT_YUV444P;
250 
251  s->frame = av_frame_alloc();
252  if (!s->frame)
253  return AVERROR(ENOMEM);
254  s->skip = av_calloc(avctx->width >> 1, avctx->height >> 1);
255  if (!s->skip)
256  return AVERROR(ENOMEM);
257 
258  return 0;
259 }
260 
261 static void decode_flush(AVCodecContext *avctx)
262 {
263  MidiVidContext *s = avctx->priv_data;
264 
265  av_frame_unref(s->frame);
266 }
267 
269 {
270  MidiVidContext *s = avctx->priv_data;
271 
272  av_frame_free(&s->frame);
273  av_freep(&s->uncompressed);
274  av_freep(&s->skip);
275 
276  return 0;
277 }
278 
280  .name = "mvdv",
281  .long_name = NULL_IF_CONFIG_SMALL("MidiVid VQ"),
282  .type = AVMEDIA_TYPE_VIDEO,
283  .id = AV_CODEC_ID_MVDV,
284  .priv_data_size = sizeof(MidiVidContext),
285  .init = decode_init,
286  .decode = decode_frame,
287  .flush = decode_flush,
288  .close = decode_close,
289  .capabilities = AV_CODEC_CAP_DR1,
290  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
291 };
static void flush(AVCodecContext *avctx)
#define av_cold
Definition: attributes.h:88
uint8_t
Libavcodec external API header.
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:192
#define flag(name)
Definition: cbs_av1.c:564
#define s(width, name)
Definition: cbs_vp9.c:257
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:2007
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
static AVFrame * frame
bitstream reader API header.
static void skip_bits_long(GetBitContext *s, int n)
Skips the specified number of bits.
Definition: get_bits.h:291
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
@ AV_CODEC_ID_MVDV
Definition: codec_id.h:297
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:50
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR(e)
Definition: error.h:43
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:553
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
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:190
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
void * av_calloc(size_t nmemb, size_t size)
Non-inlined equivalent of av_mallocz_array().
Definition: mem.c:245
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
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:317
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
@ AV_PICTURE_TYPE_P
Predicted.
Definition: avutil.h:275
const char * key
misc image utilities
int i
Definition: input.c:407
static int op(uint8_t **dst, const uint8_t *dst_end, GetByteContext *gb, int pixel, int count, int *x, int width, int linesize)
Perform decode operation.
Definition: anm.c:75
#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:49
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
static const uint16_t mask[17]
Definition: lzw.c:38
#define FFALIGN(x, a)
Definition: macros.h:48
Memory handling functions.
static ptrdiff_t lzss_uncompress(MidiVidContext *s, GetByteContext *gb, uint8_t *dst, unsigned int size)
Definition: midivid.c:154
AVCodec ff_mvdv_decoder
Definition: midivid.c:279
static av_cold int decode_close(AVCodecContext *avctx)
Definition: midivid.c:268
static av_cold int decode_init(AVCodecContext *avctx)
Definition: midivid.c:235
static void decode_flush(AVCodecContext *avctx)
Definition: midivid.c:261
static int decode_mvdv(MidiVidContext *s, AVCodecContext *avctx, AVFrame *frame)
Definition: midivid.c:47
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: midivid.c:190
const char data[16]
Definition: mxf.c:142
@ AV_PIX_FMT_YUV444P
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:71
#define s1
Definition: regdef.h:38
#define s0
Definition: regdef.h:37
main external API structure.
Definition: avcodec.h:536
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:746
int width
picture width / height.
Definition: avcodec.h:709
void * priv_data
Definition: avcodec.h:563
AVCodec.
Definition: codec.h:197
const char * name
Name of the codec implementation.
Definition: codec.h:204
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:332
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:396
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:349
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:401
This structure stores compressed data.
Definition: packet.h:346
int size
Definition: packet.h:370
uint8_t * data
Definition: packet.h:369
const uint8_t * buffer_start
Definition: bytestream.h:34
uint8_t * uncompressed
Definition: midivid.c:40
uint8_t * skip
Definition: midivid.c:42
unsigned int uncompressed_size
Definition: midivid.c:41
GetByteContext gb
Definition: midivid.c:38
AVFrame * frame
Definition: midivid.c:44
#define av_freep(p)
#define av_log(a,...)
int size
static const uint8_t offset[127][2]
Definition: vf_spp.c:107