FFmpeg coverage

GCC Code Coverage Report

Directory:	../../../ffmpeg/		Exec	Total	Coverage
File:	src/libavcodec/vmdaudio.c	Lines:	56	90	62.2 %
Date:	2021-04-22 14:24:15	Branches:	27	50	54.0 %


/*
 * Sierra VMD audio decoder
 * Copyright (c) 2004 The FFmpeg Project
 *
 * 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
 * Sierra VMD audio decoder
 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
 * for more information on the Sierra VMD format, visit:
 *   http://www.pcisys.net/~melanson/codecs/
 *
 * The audio decoder, expects each encoded data
 * chunk to be prepended with the appropriate 16-byte frame information
 * record from the VMD file. It does not require the 0x330-byte VMD file
 * header, but it does need the audio setup parameters passed in through
 * normal libavcodec API means.
 */

#include <string.h>

#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"

#include "avcodec.h"
#include "internal.h"

#define BLOCK_TYPE_AUDIO    1
#define BLOCK_TYPE_INITIAL  2
#define BLOCK_TYPE_SILENCE  3

typedef struct VmdAudioContext {
    int out_bps;
    int chunk_size;
} VmdAudioContext;

static const uint16_t vmdaudio_table[128] = {
    0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
    0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
    0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
    0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
    0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
    0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
    0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
    0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
    0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
    0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
    0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
    0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
    0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
};

static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
{
    VmdAudioContext *s = avctx->priv_data;

    if (avctx->channels < 1 || avctx->channels > 2) {
        av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
        return AVERROR(EINVAL);
    }
    if (avctx->block_align < 1 || avctx->block_align % avctx->channels ||
        avctx->block_align > INT_MAX - avctx->channels
    ) {
        av_log(avctx, AV_LOG_ERROR, "invalid block align\n");
        return AVERROR(EINVAL);
    }

    avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO :
                                                   AV_CH_LAYOUT_STEREO;

    if (avctx->bits_per_coded_sample == 16)
        avctx->sample_fmt = AV_SAMPLE_FMT_S16;
    else
        avctx->sample_fmt = AV_SAMPLE_FMT_U8;
    s->out_bps = av_get_bytes_per_sample(avctx->sample_fmt);

    s->chunk_size = avctx->block_align + avctx->channels * (s->out_bps == 2);

    av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
           "block align = %d, sample rate = %d\n",
           avctx->channels, avctx->bits_per_coded_sample, avctx->block_align,
           avctx->sample_rate);

    return 0;
}

static void decode_audio_s16(int16_t *out, const uint8_t *buf, int buf_size,
                             int channels)
{
    int ch;
    const uint8_t *buf_end = buf + buf_size;
    int predictor[2];
    int st = channels - 1;

    /* decode initial raw sample */
    for (ch = 0; ch < channels; ch++) {
        predictor[ch] = (int16_t)AV_RL16(buf);
        buf += 2;
        *out++ = predictor[ch];
    }

    /* decode DPCM samples */
    ch = 0;
    while (buf < buf_end) {
        uint8_t b = *buf++;
        if (b & 0x80)
            predictor[ch] -= vmdaudio_table[b & 0x7F];
        else
            predictor[ch] += vmdaudio_table[b];
        predictor[ch] = av_clip_int16(predictor[ch]);
        *out++ = predictor[ch];
        ch ^= st;
    }
}

static int vmdaudio_decode_frame(AVCodecContext *avctx, void *data,
                                 int *got_frame_ptr, AVPacket *avpkt)
{
    AVFrame *frame     = data;
    const uint8_t *buf = avpkt->data;
    const uint8_t *buf_end;
    int buf_size = avpkt->size;
    VmdAudioContext *s = avctx->priv_data;
    int block_type, silent_chunks, audio_chunks;
    int ret;
    uint8_t *output_samples_u8;
    int16_t *output_samples_s16;

    if (buf_size < 16) {
        av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
        *got_frame_ptr = 0;
        return buf_size;
    }

    block_type = buf[6];
    if (block_type < BLOCK_TYPE_AUDIO || block_type > BLOCK_TYPE_SILENCE) {
        av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
        return AVERROR(EINVAL);
    }
    buf      += 16;
    buf_size -= 16;

    /* get number of silent chunks */
    silent_chunks = 0;
    if (block_type == BLOCK_TYPE_INITIAL) {
        uint32_t flags;
        if (buf_size < 4) {
            av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
            return AVERROR(EINVAL);
        }
        flags         = AV_RB32(buf);
        silent_chunks = av_popcount(flags);
        buf      += 4;
        buf_size -= 4;
    } else if (block_type == BLOCK_TYPE_SILENCE) {
        silent_chunks = 1;
        buf_size = 0; // should already be zero but set it just to be sure
    }

    /* ensure output buffer is large enough */
    audio_chunks = buf_size / s->chunk_size;

    /* drop incomplete chunks */
    buf_size     = audio_chunks * s->chunk_size;

    if (silent_chunks + audio_chunks >= INT_MAX / avctx->block_align)
        return AVERROR_INVALIDDATA;

    /* get output buffer */
    frame->nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) /
                        avctx->channels;
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
        return ret;
    output_samples_u8  =            frame->data[0];
    output_samples_s16 = (int16_t *)frame->data[0];

    /* decode silent chunks */
    if (silent_chunks > 0) {
        int silent_size = avctx->block_align * silent_chunks;
        av_assert0(avctx->block_align * silent_chunks <= frame->nb_samples * avctx->channels);

        if (s->out_bps == 2) {
            memset(output_samples_s16, 0x00, silent_size * 2);
            output_samples_s16 += silent_size;
        } else {
            memset(output_samples_u8,  0x80, silent_size);
            output_samples_u8 += silent_size;
        }
    }

    /* decode audio chunks */
    if (audio_chunks > 0) {
        buf_end = buf + buf_size;
        av_assert0((buf_size & (avctx->channels > 1)) == 0);
        while (buf_end - buf >= s->chunk_size) {
            if (s->out_bps == 2) {
                decode_audio_s16(output_samples_s16, buf, s->chunk_size,
                                 avctx->channels);
                output_samples_s16 += avctx->block_align;
            } else {
                memcpy(output_samples_u8, buf, s->chunk_size);
                output_samples_u8  += avctx->block_align;
            }
            buf += s->chunk_size;
        }
    }

    *got_frame_ptr = 1;

    return avpkt->size;
}

AVCodec ff_vmdaudio_decoder = {
    .name           = "vmdaudio",
    .long_name      = NULL_IF_CONFIG_SMALL("Sierra VMD audio"),
    .type           = AVMEDIA_TYPE_AUDIO,
    .id             = AV_CODEC_ID_VMDAUDIO,
    .priv_data_size = sizeof(VmdAudioContext),
    .init           = vmdaudio_decode_init,
    .decode         = vmdaudio_decode_frame,
    .capabilities   = AV_CODEC_CAP_DR1,
};


Generated by: GCOVR (Version 4.2)

Line	Branch	Exec	Source
1			/*
2			* Sierra VMD audio decoder
3			* Copyright (c) 2004 The FFmpeg Project
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			* Sierra VMD audio decoder
25			* by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26			* for more information on the Sierra VMD format, visit:
27			* http://www.pcisys.net/~melanson/codecs/
28			*
29			* The audio decoder, expects each encoded data
30			* chunk to be prepended with the appropriate 16-byte frame information
31			* record from the VMD file. It does not require the 0x330-byte VMD file
32			* header, but it does need the audio setup parameters passed in through
33			* normal libavcodec API means.
34			*/
35
36			#include <string.h>
37
38			#include "libavutil/avassert.h"
39			#include "libavutil/channel_layout.h"
40			#include "libavutil/common.h"
41			#include "libavutil/intreadwrite.h"
42
43			#include "avcodec.h"
44			#include "internal.h"
45
46			#define BLOCK_TYPE_AUDIO 1
47			#define BLOCK_TYPE_INITIAL 2
48			#define BLOCK_TYPE_SILENCE 3
49
50			typedef struct VmdAudioContext {
51			int out_bps;
52			int chunk_size;
53			} VmdAudioContext;
54
55			static const uint16_t vmdaudio_table[128] = {
56			0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
57			0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
58			0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
59			0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
60			0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
61			0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
62			0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
63			0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
64			0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
65			0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
66			0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
67			0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
68			0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
69			};
70
71		4	static av_cold int vmdaudio_decode_init(AVCodecContext *avctx)
72			{
73		4	VmdAudioContext *s = avctx->priv_data;
74
75	✓✗✗✓	4	if (avctx->channels < 1 \|\| avctx->channels > 2) {
76			av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
77			return AVERROR(EINVAL);
78			}
79	✓✗✓✗	4	if (avctx->block_align < 1 \|\| avctx->block_align % avctx->channels \|\|
80	✗✓	4	avctx->block_align > INT_MAX - avctx->channels
81			) {
82			av_log(avctx, AV_LOG_ERROR, "invalid block align\n");
83			return AVERROR(EINVAL);
84			}
85
86	✓✗	4	avctx->channel_layout = avctx->channels == 1 ? AV_CH_LAYOUT_MONO :
87			AV_CH_LAYOUT_STEREO;
88
89	✗✓	4	if (avctx->bits_per_coded_sample == 16)
90			avctx->sample_fmt = AV_SAMPLE_FMT_S16;
91			else
92		4	avctx->sample_fmt = AV_SAMPLE_FMT_U8;
93		4	s->out_bps = av_get_bytes_per_sample(avctx->sample_fmt);
94
95		4	s->chunk_size = avctx->block_align + avctx->channels * (s->out_bps == 2);
96
97		4	av_log(avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, "
98			"block align = %d, sample rate = %d\n",
99			avctx->channels, avctx->bits_per_coded_sample, avctx->block_align,
100			avctx->sample_rate);
101
102		4	return 0;
103			}
104
105			static void decode_audio_s16(int16_t out, const uint8_t buf, int buf_size,
106			int channels)
107			{
108			int ch;
109			const uint8_t *buf_end = buf + buf_size;
110			int predictor[2];
111			int st = channels - 1;
112
113			/* decode initial raw sample */
114			for (ch = 0; ch < channels; ch++) {
115			predictor[ch] = (int16_t)AV_RL16(buf);
116			buf += 2;
117			*out++ = predictor[ch];
118			}
119
120			/* decode DPCM samples */
121			ch = 0;
122			while (buf < buf_end) {
123			uint8_t b = *buf++;
124			if (b & 0x80)
125			predictor[ch] -= vmdaudio_table[b & 0x7F];
126			else
127			predictor[ch] += vmdaudio_table[b];
128			predictor[ch] = av_clip_int16(predictor[ch]);
129			*out++ = predictor[ch];
130			ch ^= st;
131			}
132			}
133
134		215	static int vmdaudio_decode_frame(AVCodecContext avctx, void data,
135			int got_frame_ptr, AVPacket avpkt)
136			{
137		215	AVFrame *frame = data;
138		215	const uint8_t *buf = avpkt->data;
139			const uint8_t *buf_end;
140		215	int buf_size = avpkt->size;
141		215	VmdAudioContext *s = avctx->priv_data;
142			int block_type, silent_chunks, audio_chunks;
143			int ret;
144			uint8_t *output_samples_u8;
145			int16_t *output_samples_s16;
146
147	✗✓	215	if (buf_size < 16) {
148			av_log(avctx, AV_LOG_WARNING, "skipping small junk packet\n");
149			*got_frame_ptr = 0;
150			return buf_size;
151			}
152
153		215	block_type = buf[6];
154	✓✗✗✓	215	if (block_type < BLOCK_TYPE_AUDIO \|\| block_type > BLOCK_TYPE_SILENCE) {
155			av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
156			return AVERROR(EINVAL);
157			}
158		215	buf += 16;
159		215	buf_size -= 16;
160
161			/* get number of silent chunks */
162		215	silent_chunks = 0;
163	✓✓	215	if (block_type == BLOCK_TYPE_INITIAL) {
164			uint32_t flags;
165	✗✓	1	if (buf_size < 4) {
166			av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
167			return AVERROR(EINVAL);
168			}
169		1	flags = AV_RB32(buf);
170		1	silent_chunks = av_popcount(flags);
171		1	buf += 4;
172		1	buf_size -= 4;
173	✓✓	214	} else if (block_type == BLOCK_TYPE_SILENCE) {
174		29	silent_chunks = 1;
175		29	buf_size = 0; // should already be zero but set it just to be sure
176			}
177
178			/* ensure output buffer is large enough */
179		215	audio_chunks = buf_size / s->chunk_size;
180
181			/* drop incomplete chunks */
182		215	buf_size = audio_chunks * s->chunk_size;
183
184	✗✓	215	if (silent_chunks + audio_chunks >= INT_MAX / avctx->block_align)
185			return AVERROR_INVALIDDATA;
186
187			/* get output buffer */
188		215	frame->nb_samples = ((silent_chunks + audio_chunks) * avctx->block_align) /
189		215	avctx->channels;
190	✗✓	215	if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
191			return ret;
192		215	output_samples_u8 = frame->data[0];
193		215	output_samples_s16 = (int16_t *)frame->data[0];
194
195			/* decode silent chunks */
196	✓✓	215	if (silent_chunks > 0) {
197		29	int silent_size = avctx->block_align * silent_chunks;
198	✗✓	29	av_assert0(avctx->block_align * silent_chunks <= frame->nb_samples * avctx->channels);
199
200	✗✓	29	if (s->out_bps == 2) {
201			memset(output_samples_s16, 0x00, silent_size * 2);
202			output_samples_s16 += silent_size;
203			} else {
204		29	memset(output_samples_u8, 0x80, silent_size);
205		29	output_samples_u8 += silent_size;
206			}
207			}
208
209			/* decode audio chunks */
210	✓✓	215	if (audio_chunks > 0) {
211		186	buf_end = buf + buf_size;
212	✗✓	186	av_assert0((buf_size & (avctx->channels > 1)) == 0);
213	✓✓	399	while (buf_end - buf >= s->chunk_size) {
214	✗✓	213	if (s->out_bps == 2) {
215			decode_audio_s16(output_samples_s16, buf, s->chunk_size,
216			avctx->channels);
217			output_samples_s16 += avctx->block_align;
218			} else {
219		213	memcpy(output_samples_u8, buf, s->chunk_size);
220		213	output_samples_u8 += avctx->block_align;
221			}
222		213	buf += s->chunk_size;
223			}
224			}
225
226		215	*got_frame_ptr = 1;
227
228		215	return avpkt->size;
229			}
230
231			AVCodec ff_vmdaudio_decoder = {
232			.name = "vmdaudio",
233			.long_name = NULL_IF_CONFIG_SMALL("Sierra VMD audio"),
234			.type = AVMEDIA_TYPE_AUDIO,
235			.id = AV_CODEC_ID_VMDAUDIO,
236			.priv_data_size = sizeof(VmdAudioContext),
237			.init = vmdaudio_decode_init,
238			.decode = vmdaudio_decode_frame,
239			.capabilities = AV_CODEC_CAP_DR1,
240			};