FFmpeg coverage

Line	Branch	Exec	Source
1			/*
2			* Bonk audio decoder
3			*
4			* This file is part of FFmpeg.
5			*
6			* FFmpeg is free software; you can redistribute it and/or
7			* modify it under the terms of the GNU Lesser General Public
8			* License as published by the Free Software Foundation; either
9			* version 2.1 of the License, or (at your option) any later version.
10			*
11			* FFmpeg is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14			* Lesser General Public License for more details.
15			*
16			* You should have received a copy of the GNU Lesser General Public
17			* License along with FFmpeg; if not, write to the Free Software
18			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19			*/
20
21			#include "libavutil/intreadwrite.h"
22			#include "libavutil/mem.h"
23			#include "avcodec.h"
24			#include "codec_internal.h"
25			#include "decode.h"
26			#define BITSTREAM_READER_LE
27			#include "get_bits.h"
28
29			typedef struct BitCount {
30			uint8_t bit;
31			unsigned count;
32			} BitCount;
33
34			typedef struct BonkContext {
35			GetBitContext gb;
36			int skip;
37
38			uint8_t *bitstream;
39			int64_t max_framesize;
40			int bitstream_size;
41			int bitstream_index;
42
43			uint64_t nb_samples;
44			int lossless;
45			int mid_side;
46			int n_taps;
47			int down_sampling;
48			int samples_per_packet;
49
50			int state[2][2048], k[2048];
51			int *samples[2];
52			int *input_samples;
53			uint8_t quant[2048];
54			BitCount *bits;
55			} BonkContext;
56
57		✗	static av_cold int bonk_close(AVCodecContext *avctx)
58			{
59		✗	BonkContext *s = avctx->priv_data;
60
61		✗	av_freep(&s->bitstream);
62		✗	av_freep(&s->input_samples);
63		✗	av_freep(&s->samples[0]);
64		✗	av_freep(&s->samples[1]);
65		✗	av_freep(&s->bits);
66		✗	s->bitstream_size = 0;
67
68		✗	return 0;
69			}
70
71		✗	static av_cold int bonk_init(AVCodecContext *avctx)
72			{
73		✗	BonkContext *s = avctx->priv_data;
74
75		✗	avctx->sample_fmt = AV_SAMPLE_FMT_S16P;
76		✗	if (avctx->extradata_size < 17)
77		✗	return AVERROR(EINVAL);
78
79		✗	if (avctx->extradata[0]) {
80		✗	av_log(avctx, AV_LOG_ERROR, "Unsupported version.\n");
81		✗	return AVERROR_INVALIDDATA;
82			}
83
84		✗	if (avctx->ch_layout.nb_channels < 1 || avctx->ch_layout.nb_channels > 2)
85		✗	return AVERROR_INVALIDDATA;
86
87		✗	s->nb_samples = AV_RL32(avctx->extradata + 1) / avctx->ch_layout.nb_channels;
88		✗	if (!s->nb_samples)
89		✗	s->nb_samples = UINT64_MAX;
90		✗	s->lossless = avctx->extradata[10] != 0;
91		✗	s->mid_side = avctx->extradata[11] != 0;
92		✗	s->n_taps = AV_RL16(avctx->extradata + 12);
93		✗	if (!s->n_taps || s->n_taps > 2048)
94		✗	return AVERROR(EINVAL);
95
96		✗	s->down_sampling = avctx->extradata[14];
97		✗	if (!s->down_sampling)
98		✗	return AVERROR(EINVAL);
99
100		✗	s->samples_per_packet = AV_RL16(avctx->extradata + 15);
101		✗	if (!s->samples_per_packet)
102		✗	return AVERROR(EINVAL);
103
104		✗	if (s->down_sampling * s->samples_per_packet < s->n_taps)
105		✗	return AVERROR_INVALIDDATA;
106
107		✗	s->max_framesize = s->samples_per_packet * avctx->ch_layout.nb_channels * s->down_sampling * 16LL;
108		✗	if (s->max_framesize > (INT32_MAX - AV_INPUT_BUFFER_PADDING_SIZE) / 8)
109		✗	return AVERROR_INVALIDDATA;
110
111		✗	s->bitstream = av_calloc(s->max_framesize + AV_INPUT_BUFFER_PADDING_SIZE, sizeof(*s->bitstream));
112		✗	if (!s->bitstream)
113		✗	return AVERROR(ENOMEM);
114
115		✗	s->input_samples = av_calloc(s->samples_per_packet, sizeof(*s->input_samples));
116		✗	if (!s->input_samples)
117		✗	return AVERROR(ENOMEM);
118
119		✗	s->samples[0] = av_calloc(s->samples_per_packet * s->down_sampling, sizeof(*s->samples[0]));
120		✗	s->samples[1] = av_calloc(s->samples_per_packet * s->down_sampling, sizeof(*s->samples[0]));
121		✗	if (!s->samples[0] || !s->samples[1])
122		✗	return AVERROR(ENOMEM);
123
124		✗	s->bits = av_calloc(s->max_framesize * 8, sizeof(*s->bits));
125		✗	if (!s->bits)
126		✗	return AVERROR(ENOMEM);
127
128		✗	for (int i = 0; i < 512; i++) {
129		✗	s->quant[i] = sqrt(i + 1);
130			}
131
132		✗	return 0;
133			}
134
135		✗	static unsigned read_uint_max(BonkContext *s, uint32_t max)
136			{
137		✗	unsigned value = 0;
138
139		✗	if (max == 0)
140		✗	return 0;
141
142		✗	av_assert0(max >> 31 == 0);
143
144		✗	for (unsigned i = 1; i <= max - value; i+=i)
145		✗	if (get_bits1(&s->gb))
146		✗	value += i;
147
148		✗	return value;
149			}
150
151		✗	static int intlist_read(BonkContext *s, int *buf, int entries, int base_2_part)
152			{
153		✗	int i, low_bits = 0, x = 0, max_x;
154		✗	int n_zeros = 0, step = 256, dominant = 0;
155		✗	int pos = 0, level = 0;
156		✗	BitCount *bits = s->bits;
157		✗	int passes = 1;
158
159		✗	memset(buf, 0, entries * sizeof(*buf));
160		✗	if (base_2_part) {
161		✗	low_bits = get_bits(&s->gb, 4);
162
163		✗	if (low_bits)
164		✗	for (i = 0; i < entries; i++)
165		✗	buf[i] = get_bits(&s->gb, low_bits);
166			}
167
168		✗	while (n_zeros < entries) {
169		✗	int steplet = step >> 8;
170
171		✗	if (get_bits_left(&s->gb) <= 0)
172		✗	return AVERROR_INVALIDDATA;
173
174		✗	if (!get_bits1(&s->gb)) {
175		✗	av_assert0(steplet >= 0);
176
177		✗	if (steplet > 0) {
178		✗	bits[x ].bit = dominant;
179		✗	bits[x++].count = steplet;
180			}
181
182		✗	if (!dominant)
183		✗	n_zeros += steplet;
184
185		✗	if (step > INT32_MAX*8LL/9 + 1)
186		✗	return AVERROR_INVALIDDATA;
187		✗	step += step / 8;
188		✗	} else if (steplet > 0) {
189		✗	int actual_run = read_uint_max(s, steplet - 1);
190
191		✗	av_assert0(actual_run >= 0);
192
193		✗	if (actual_run > 0) {
194		✗	bits[x ].bit = dominant;
195		✗	bits[x++].count = actual_run;
196			}
197
198		✗	bits[x ].bit = !dominant;
199		✗	bits[x++].count = 1;
200
201		✗	if (!dominant)
202		✗	n_zeros += actual_run;
203			else
204		✗	n_zeros++;
205
206		✗	step -= step / 8;
207			}
208
209		✗	if (step < 256) {
210		✗	step = 65536 / step;
211		✗	dominant = !dominant;
212			}
213			}
214
215		✗	max_x = x;
216		✗	x = 0;
217		✗	n_zeros = 0;
218		✗	for (i = 0; n_zeros < entries; i++) {
219		✗	if (x >= max_x)
220		✗	return AVERROR_INVALIDDATA;
221
222		✗	if (pos >= entries) {
223		✗	pos = 0;
224		✗	level += passes << low_bits;
225		✗	passes = 1;
226		✗	if (bits[x].bit && bits[x].count > entries - n_zeros)
227		✗	passes = bits[x].count / (entries - n_zeros);
228			}
229
230		✗	if (level > 1 << 16)
231		✗	return AVERROR_INVALIDDATA;
232
233		✗	if (buf[pos] >= level) {
234		✗	if (bits[x].bit)
235		✗	buf[pos] += passes << low_bits;
236			else
237		✗	n_zeros++;
238
239			av_assert1(bits[x].count >= passes);
240		✗	bits[x].count -= passes;
241		✗	x += bits[x].count == 0;
242			}
243
244		✗	pos++;
245			}
246
247		✗	for (i = 0; i < entries; i++) {
248		✗	if (buf[i] && get_bits1(&s->gb)) {
249		✗	buf[i] = -buf[i];
250			}
251			}
252
253		✗	return 0;
254			}
255
256		✗	static inline int shift_down(int a, int b)
257			{
258		✗	return (a >> b) + (a < 0);
259			}
260
261		✗	static inline int shift(int a, int b)
262			{
263		✗	return a + (1 << b - 1) >> b;
264			}
265
266			#define LATTICE_SHIFT 10
267			#define SAMPLE_SHIFT 4
268			#define SAMPLE_FACTOR (1 << SAMPLE_SHIFT)
269
270		✗	static int predictor_calc_error(int *k, int *state, int order, int error)
271			{
272		✗	int i, x = error - (unsigned)shift_down(k[order-1] * (unsigned)state[order-1], LATTICE_SHIFT);
273		✗	int *k_ptr = &(k[order-2]),
274		✗	*state_ptr = &(state[order-2]);
275
276		✗	for (i = order-2; i >= 0; i--, k_ptr--, state_ptr--) {
277		✗	unsigned k_value = *k_ptr, state_value = *state_ptr;
278
279		✗	x -= (unsigned) shift_down(k_value * (unsigned)state_value, LATTICE_SHIFT);
280		✗	state_ptr[1] = state_value + shift_down(k_value * x, LATTICE_SHIFT);
281			}
282
283			// don't drift too far, to avoid overflows
284		✗	x = av_clip(x, -(SAMPLE_FACTOR << 16), SAMPLE_FACTOR << 16);
285
286		✗	state[0] = x;
287
288		✗	return x;
289			}
290
291		✗	static void predictor_init_state(int *k, unsigned *state, int order)
292			{
293		✗	for (int i = order - 2; i >= 0; i--) {
294		✗	unsigned x = state[i];
295
296		✗	for (int j = 0, p = i + 1; p < order; j++, p++) {
297		✗	int tmp = x + shift_down(k[j] * state[p], LATTICE_SHIFT);
298
299		✗	state[p] += shift_down(k[j] * x, LATTICE_SHIFT);
300		✗	x = tmp;
301			}
302			}
303		✗	}
304
305		✗	static int bonk_decode(AVCodecContext *avctx, AVFrame *frame,
306			int *got_frame_ptr, AVPacket *pkt)
307			{
308		✗	BonkContext *s = avctx->priv_data;
309		✗	GetBitContext *gb = &s->gb;
310			const uint8_t *buf;
311			int quant, n, buf_size, input_buf_size;
312		✗	int ret = AVERROR_INVALIDDATA;
313
314		✗	if ((!pkt->size && !s->bitstream_size) || s->nb_samples == 0) {
315		✗	*got_frame_ptr = 0;
316		✗	return pkt->size;
317			}
318
319		✗	buf_size = FFMIN(pkt->size, s->max_framesize - s->bitstream_size);
320		✗	input_buf_size = buf_size;
321		✗	if (s->bitstream_index + s->bitstream_size + buf_size + AV_INPUT_BUFFER_PADDING_SIZE > s->max_framesize) {
322		✗	memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
323		✗	s->bitstream_index = 0;
324			}
325		✗	if (pkt->data)
326		✗	memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], pkt->data, buf_size);
327		✗	buf = &s->bitstream[s->bitstream_index];
328		✗	buf_size += s->bitstream_size;
329		✗	s->bitstream_size = buf_size;
330		✗	if (buf_size < s->max_framesize && pkt->data) {
331		✗	*got_frame_ptr = 0;
332		✗	return input_buf_size;
333			}
334
335		✗	frame->nb_samples = FFMIN(s->samples_per_packet * s->down_sampling, s->nb_samples);
336		✗	if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
337		✗	goto fail;
338
339		✗	if ((ret = init_get_bits8(gb, buf, buf_size)) < 0)
340		✗	goto fail;
341
342		✗	skip_bits(gb, s->skip);
343		✗	if ((ret = intlist_read(s, s->k, s->n_taps, 0)) < 0)
344		✗	goto fail;
345
346		✗	for (int i = 0; i < s->n_taps; i++)
347		✗	s->k[i] *= s->quant[i];
348		✗	quant = s->lossless ? 1 : get_bits(&s->gb, 16) * SAMPLE_FACTOR;
349
350		✗	for (int ch = 0; ch < avctx->ch_layout.nb_channels; ch++) {
351		✗	const int samples_per_packet = s->samples_per_packet;
352		✗	const int down_sampling = s->down_sampling;
353		✗	const int offset = samples_per_packet * down_sampling - 1;
354		✗	int *state = s->state[ch];
355		✗	int *sample = s->samples[ch];
356
357		✗	predictor_init_state(s->k, state, s->n_taps);
358		✗	if ((ret = intlist_read(s, s->input_samples, samples_per_packet, 1)) < 0)
359		✗	goto fail;
360
361		✗	for (int i = 0; i < samples_per_packet; i++) {
362		✗	for (int j = 0; j < s->down_sampling - 1; j++) {
363		✗	sample[0] = predictor_calc_error(s->k, state, s->n_taps, 0);
364		✗	sample++;
365			}
366
367		✗	sample[0] = predictor_calc_error(s->k, state, s->n_taps, s->input_samples[i] * (unsigned)quant);
368		✗	sample++;
369			}
370
371		✗	sample = s->samples[ch];
372		✗	for (int i = 0; i < s->n_taps; i++)
373		✗	state[i] = sample[offset - i];
374			}
375
376		✗	if (s->mid_side && avctx->ch_layout.nb_channels == 2) {
377		✗	for (int i = 0; i < frame->nb_samples; i++) {
378		✗	s->samples[1][i] += shift(s->samples[0][i], 1);
379		✗	s->samples[0][i] -= s->samples[1][i];
380			}
381			}
382
383		✗	if (!s->lossless) {
384		✗	for (int ch = 0; ch < avctx->ch_layout.nb_channels; ch++) {
385		✗	int *samples = s->samples[ch];
386		✗	for (int i = 0; i < frame->nb_samples; i++)
387		✗	samples[i] = shift(samples[i], 4);
388			}
389			}
390
391		✗	for (int ch = 0; ch < avctx->ch_layout.nb_channels; ch++) {
392		✗	int16_t *osamples = (int16_t *)frame->extended_data[ch];
393		✗	int *samples = s->samples[ch];
394		✗	for (int i = 0; i < frame->nb_samples; i++)
395		✗	osamples[i] = av_clip_int16(samples[i]);
396			}
397
398		✗	s->nb_samples -= frame->nb_samples;
399
400		✗	s->skip = get_bits_count(gb) - 8 * (get_bits_count(gb) / 8);
401		✗	n = get_bits_count(gb) / 8;
402
403		✗	if (n > buf_size) {
404		✗	fail:
405		✗	s->bitstream_size = 0;
406		✗	s->bitstream_index = 0;
407		✗	return AVERROR_INVALIDDATA;
408			}
409
410		✗	*got_frame_ptr = 1;
411
412		✗	if (s->bitstream_size) {
413		✗	s->bitstream_index += n;
414		✗	s->bitstream_size -= n;
415		✗	return input_buf_size;
416			}
417		✗	return n;
418			}
419
420			const FFCodec ff_bonk_decoder = {
421			.p.name = "bonk",
422			CODEC_LONG_NAME("Bonk audio"),
423			.p.type = AVMEDIA_TYPE_AUDIO,
424			.p.id = AV_CODEC_ID_BONK,
425			.priv_data_size = sizeof(BonkContext),
426			.init = bonk_init,
427			FF_CODEC_DECODE_CB(bonk_decode),
428			.close = bonk_close,
429			.p.capabilities = AV_CODEC_CAP_DELAY |
430			AV_CODEC_CAP_DR1,
431			.caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
432			};
433