1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
|
/*
* Vidvox Hap decoder
* Copyright (C) 2015 Vittorio Giovara <vittorio.giovara@gmail.com>
* Copyright (C) 2015 Tom Butterworth <bangnoise@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Hap decoder
*
* Fourcc: Hap1, Hap5, HapY
*
* https://github.com/Vidvox/hap/blob/master/documentation/HapVideoDRAFT.md
*/
#include <stdint.h>
#include "libavutil/imgutils.h"
#include "avcodec.h"
#include "bytestream.h"
#include "hap.h"
#include "internal.h"
#include "snappy.h"
#include "texturedsp.h"
#include "thread.h"
#include "memory.h"
/* The first three bytes are the size of the section past the header, or zero
* if the length is stored in the next long word. The fourth byte in the first
* long word indicates the type of the current section. */
static int parse_section_header(GetByteContext *gbc, int *section_size,
enum HapSectionType *section_type)
{
if (bytestream2_get_bytes_left(gbc) < 4)
return AVERROR_INVALIDDATA;
*section_size = bytestream2_get_le24(gbc);
*section_type = bytestream2_get_byte(gbc);
if (*section_size == 0) {
if (bytestream2_get_bytes_left(gbc) < 4)
return AVERROR_INVALIDDATA;
*section_size = bytestream2_get_le32(gbc);
}
if (*section_size > bytestream2_get_bytes_left(gbc))
return AVERROR_INVALIDDATA;
else
return 0;
}
static int hap_parse_decode_instructions(HapContext *ctx, int size)
{
GetByteContext *gbc = &ctx->gbc;
int section_size;
enum HapSectionType section_type;
int is_first_table = 1, had_offsets = 0, had_compressors = 0, had_sizes = 0;
int i, ret;
while (size > 0) {
int stream_remaining = bytestream2_get_bytes_left(gbc);
ret = parse_section_header(gbc, §ion_size, §ion_type);
if (ret != 0)
return ret;
size -= stream_remaining - bytestream2_get_bytes_left(gbc);
switch (section_type) {
case HAP_ST_COMPRESSOR_TABLE:
ret = ff_hap_set_chunk_count(ctx, section_size, is_first_table);
if (ret != 0)
return ret;
for (i = 0; i < section_size; i++) {
ctx->chunks[i].compressor = bytestream2_get_byte(gbc) << 4;
}
had_compressors = 1;
is_first_table = 0;
break;
case HAP_ST_SIZE_TABLE:
ret = ff_hap_set_chunk_count(ctx, section_size / 4, is_first_table);
if (ret != 0)
return ret;
for (i = 0; i < section_size / 4; i++) {
ctx->chunks[i].compressed_size = bytestream2_get_le32(gbc);
}
had_sizes = 1;
is_first_table = 0;
break;
case HAP_ST_OFFSET_TABLE:
ret = ff_hap_set_chunk_count(ctx, section_size / 4, is_first_table);
if (ret != 0)
return ret;
for (i = 0; i < section_size / 4; i++) {
ctx->chunks[i].compressed_offset = bytestream2_get_le32(gbc);
}
had_offsets = 1;
is_first_table = 0;
break;
default:
break;
}
size -= section_size;
}
if (!had_sizes || !had_compressors)
return AVERROR_INVALIDDATA;
/* The offsets table is optional. If not present than calculate offsets by
* summing the sizes of preceding chunks. */
if (!had_offsets) {
size_t running_size = 0;
for (i = 0; i < ctx->chunk_count; i++) {
ctx->chunks[i].compressed_offset = running_size;
running_size += ctx->chunks[i].compressed_size;
}
}
return 0;
}
static int hap_can_use_tex_in_place(HapContext *ctx)
{
int i;
size_t running_offset = 0;
for (i = 0; i < ctx->chunk_count; i++) {
if (ctx->chunks[i].compressed_offset != running_offset
|| ctx->chunks[i].compressor != HAP_COMP_NONE)
return 0;
running_offset += ctx->chunks[i].compressed_size;
}
return 1;
}
static int hap_parse_frame_header(AVCodecContext *avctx)
{
HapContext *ctx = avctx->priv_data;
GetByteContext *gbc = &ctx->gbc;
int section_size;
enum HapSectionType section_type;
const char *compressorstr;
int i, ret;
ret = parse_section_header(gbc, §ion_size, §ion_type);
if (ret != 0)
return ret;
if ((avctx->codec_tag == MKTAG('H','a','p','1') && (section_type & 0x0F) != HAP_FMT_RGBDXT1)
|| (avctx->codec_tag == MKTAG('H','a','p','5') && (section_type & 0x0F) != HAP_FMT_RGBADXT5)
|| (avctx->codec_tag == MKTAG('H','a','p','Y') && (section_type & 0x0F) != HAP_FMT_YCOCGDXT5)) {
av_log(avctx, AV_LOG_ERROR, "Invalid texture format %#04x.\n", section_type & 0x0F);
return AVERROR_INVALIDDATA;
}
switch (section_type & 0xF0) {
case HAP_COMP_NONE:
case HAP_COMP_SNAPPY:
ret = ff_hap_set_chunk_count(ctx, 1, 1);
if (ret == 0) {
ctx->chunks[0].compressor = section_type & 0xF0;
ctx->chunks[0].compressed_offset = 0;
ctx->chunks[0].compressed_size = section_size;
}
if (ctx->chunks[0].compressor == HAP_COMP_NONE) {
compressorstr = "none";
} else {
compressorstr = "snappy";
}
break;
case HAP_COMP_COMPLEX:
ret = parse_section_header(gbc, §ion_size, §ion_type);
if (ret == 0 && section_type != HAP_ST_DECODE_INSTRUCTIONS)
ret = AVERROR_INVALIDDATA;
if (ret == 0)
ret = hap_parse_decode_instructions(ctx, section_size);
compressorstr = "complex";
break;
default:
ret = AVERROR_INVALIDDATA;
break;
}
if (ret != 0)
return ret;
/* Check the frame is valid and read the uncompressed chunk sizes */
ctx->tex_size = 0;
for (i = 0; i < ctx->chunk_count; i++) {
HapChunk *chunk = &ctx->chunks[i];
/* Check the compressed buffer is valid */
if (chunk->compressed_offset + chunk->compressed_size > bytestream2_get_bytes_left(gbc))
return AVERROR_INVALIDDATA;
/* Chunks are unpacked sequentially, ctx->tex_size is the uncompressed
* size thus far */
chunk->uncompressed_offset = ctx->tex_size;
/* Fill out uncompressed size */
if (chunk->compressor == HAP_COMP_SNAPPY) {
GetByteContext gbc_tmp;
int64_t uncompressed_size;
bytestream2_init(&gbc_tmp, gbc->buffer + chunk->compressed_offset,
chunk->compressed_size);
uncompressed_size = ff_snappy_peek_uncompressed_length(&gbc_tmp);
if (uncompressed_size < 0) {
return uncompressed_size;
}
chunk->uncompressed_size = uncompressed_size;
} else if (chunk->compressor == HAP_COMP_NONE) {
chunk->uncompressed_size = chunk->compressed_size;
} else {
return AVERROR_INVALIDDATA;
}
ctx->tex_size += chunk->uncompressed_size;
}
av_log(avctx, AV_LOG_DEBUG, "%s compressor\n", compressorstr);
return ret;
}
static int decompress_chunks_thread(AVCodecContext *avctx, void *arg,
int chunk_nb, int thread_nb)
{
HapContext *ctx = avctx->priv_data;
HapChunk *chunk = &ctx->chunks[chunk_nb];
GetByteContext gbc;
uint8_t *dst = ctx->tex_buf + chunk->uncompressed_offset;
bytestream2_init(&gbc, ctx->gbc.buffer + chunk->compressed_offset, chunk->compressed_size);
if (chunk->compressor == HAP_COMP_SNAPPY) {
int ret;
int64_t uncompressed_size = ctx->tex_size;
/* Uncompress the frame */
ret = ff_snappy_uncompress(&gbc, dst, &uncompressed_size);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Snappy uncompress error\n");
return ret;
}
} else if (chunk->compressor == HAP_COMP_NONE) {
bytestream2_get_buffer(&gbc, dst, chunk->compressed_size);
}
return 0;
}
static int decompress_texture_thread(AVCodecContext *avctx, void *arg,
int slice, int thread_nb)
{
HapContext *ctx = avctx->priv_data;
AVFrame *frame = arg;
const uint8_t *d = ctx->tex_data;
int w_block = avctx->coded_width / TEXTURE_BLOCK_W;
int h_block = avctx->coded_height / TEXTURE_BLOCK_H;
int x, y;
int start_slice, end_slice;
int base_blocks_per_slice = h_block / ctx->slice_count;
int remainder_blocks = h_block % ctx->slice_count;
/* When the frame height (in blocks) doesn't divide evenly between the
* number of slices, spread the remaining blocks evenly between the first
* operations */
start_slice = slice * base_blocks_per_slice;
/* Add any extra blocks (one per slice) that have been added before this slice */
start_slice += FFMIN(slice, remainder_blocks);
end_slice = start_slice + base_blocks_per_slice;
/* Add an extra block if there are still remainder blocks to be accounted for */
if (slice < remainder_blocks)
end_slice++;
for (y = start_slice; y < end_slice; y++) {
uint8_t *p = frame->data[0] + y * frame->linesize[0] * TEXTURE_BLOCK_H;
int off = y * w_block;
for (x = 0; x < w_block; x++) {
ctx->tex_fun(p + x * 16, frame->linesize[0],
d + (off + x) * ctx->tex_rat);
}
}
return 0;
}
static int hap_decode(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
HapContext *ctx = avctx->priv_data;
ThreadFrame tframe;
int ret, i;
int tex_size;
bytestream2_init(&ctx->gbc, avpkt->data, avpkt->size);
/* Check for section header */
ret = hap_parse_frame_header(avctx);
if (ret < 0)
return ret;
/* Get the output frame ready to receive data */
tframe.f = data;
ret = ff_thread_get_buffer(avctx, &tframe, 0);
if (ret < 0)
return ret;
if (avctx->codec->update_thread_context)
ff_thread_finish_setup(avctx);
/* Unpack the DXT texture */
if (hap_can_use_tex_in_place(ctx)) {
/* Only DXTC texture compression in a contiguous block */
ctx->tex_data = ctx->gbc.buffer;
tex_size = bytestream2_get_bytes_left(&ctx->gbc);
} else {
/* Perform the second-stage decompression */
ret = av_reallocp(&ctx->tex_buf, ctx->tex_size);
if (ret < 0)
return ret;
avctx->execute2(avctx, decompress_chunks_thread, NULL,
ctx->chunk_results, ctx->chunk_count);
for (i = 0; i < ctx->chunk_count; i++) {
if (ctx->chunk_results[i] < 0)
return ctx->chunk_results[i];
}
ctx->tex_data = ctx->tex_buf;
tex_size = ctx->tex_size;
}
if (tex_size < (avctx->coded_width / TEXTURE_BLOCK_W)
*(avctx->coded_height / TEXTURE_BLOCK_H)
*ctx->tex_rat) {
av_log(avctx, AV_LOG_ERROR, "Insufficient data\n");
return AVERROR_INVALIDDATA;
}
/* Use the decompress function on the texture, one block per thread */
avctx->execute2(avctx, decompress_texture_thread, tframe.f, NULL, ctx->slice_count);
/* Frame is ready to be output */
tframe.f->pict_type = AV_PICTURE_TYPE_I;
tframe.f->key_frame = 1;
*got_frame = 1;
return avpkt->size;
}
static av_cold int hap_init(AVCodecContext *avctx)
{
HapContext *ctx = avctx->priv_data;
const char *texture_name;
int ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
if (ret < 0) {
av_log(avctx, AV_LOG_ERROR, "Invalid video size %dx%d.\n",
avctx->width, avctx->height);
return ret;
}
/* Since codec is based on 4x4 blocks, size is aligned to 4 */
avctx->coded_width = FFALIGN(avctx->width, TEXTURE_BLOCK_W);
avctx->coded_height = FFALIGN(avctx->height, TEXTURE_BLOCK_H);
/* Technically only one mode has alpha, but 32 bits are easier to handle */
avctx->pix_fmt = AV_PIX_FMT_RGBA;
ff_texturedsp_init(&ctx->dxtc);
switch (avctx->codec_tag) {
case MKTAG('H','a','p','1'):
texture_name = "DXT1";
ctx->tex_rat = 8;
ctx->tex_fun = ctx->dxtc.dxt1_block;
break;
case MKTAG('H','a','p','5'):
texture_name = "DXT5";
ctx->tex_rat = 16;
ctx->tex_fun = ctx->dxtc.dxt5_block;
break;
case MKTAG('H','a','p','Y'):
texture_name = "DXT5-YCoCg-scaled";
ctx->tex_rat = 16;
ctx->tex_fun = ctx->dxtc.dxt5ys_block;
break;
default:
return AVERROR_DECODER_NOT_FOUND;
}
av_log(avctx, AV_LOG_DEBUG, "%s texture\n", texture_name);
ctx->slice_count = av_clip(avctx->thread_count, 1,
avctx->coded_height / TEXTURE_BLOCK_H);
return 0;
}
static av_cold int hap_close(AVCodecContext *avctx)
{
HapContext *ctx = avctx->priv_data;
ff_hap_free_context(ctx);
return 0;
}
AVCodec ff_hap_decoder = {
.name = "hap",
.long_name = NULL_IF_CONFIG_SMALL("Vidvox Hap decoder"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_HAP,
.init = hap_init,
.decode = hap_decode,
.close = hap_close,
.priv_data_size = sizeof(HapContext),
.capabilities = AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_SLICE_THREADS |
AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE |
FF_CODEC_CAP_INIT_CLEANUP,
};
|