c++ - 来自捕获的 PCM 样本数据的 WAV 文件

Question

我使用 NI 数据采集模块以 48ksps 的速度“现场”捕获了数 Gb 的样本数据。我想根据这些数据创建一个 WAV 文件。

我之前使用 MATLAB 加载数据，将其标准化为 16 位 PCM 范围，然后将其写为 WAV 文件。然而，MATLAB 在文件大小方面犹豫不决，因为它在“内存中”执行所有操作。

理想情况下，我会使用 C++ 或 C(C# 是一个选项)执行此操作，或者如果有现成的实用程序，我会使用它。是否有一种简单的方法(即现有库)获取原始 PCM 缓冲区、指定采样率、位深度并将其打包到 WAV 文件中？

要处理大型数据集，它需要能够以 block 的形式附加数据，因为不一定可以将整个数据集读入内存。

我知道我可以使用格式规范从头开始做这件事，但我不想重新发明轮子，或者如果我能帮忙的话，也不想花时间修复错误。

Answer 1

有趣的是，我在代码的 stackoverflow 解析中发现了一个错误，它不支持行尾的\字符，如下所示，很遗憾

//stolen from OGG Vorbis pcm to wav conversion rountines, sorry
#define VERSIONSTRING "OggDec 1.0\n"

static int quiet = 0;
static int bits = 16;
static int endian = 0;
static int raw = 0;
static int sign = 1;
unsigned char headbuf[44];  /* The whole buffer */







#define WRITE_U32(buf, x) *(buf)     = (unsigned char)((x)&0xff);\
                          *((buf)+1) = (unsigned char)(((x)>>8)&0xff);\
                          *((buf)+2) = (unsigned char)(((x)>>16)&0xff);\
                          *((buf)+3) = (unsigned char)(((x)>>24)&0xff);

#define WRITE_U16(buf, x) *(buf)     = (unsigned char)((x)&0xff);\
                          *((buf)+1) = (unsigned char)(((x)>>8)&0xff);

/*
 * Some of this based on ao/src/ao_wav.c
 */
static int
write_prelim_header (FILE * out, int channels, int samplerate)
{

  int knownlength = 0;

  unsigned int size = 0x7fffffff;
  // int channels = 2;
  // int samplerate = 44100;//change this to 48000
  int bytespersec = channels * samplerate * bits / 8;
  int align = channels * bits / 8;
  int samplesize = bits;

  if (knownlength)
    size = (unsigned int) knownlength;

  memcpy (headbuf, "RIFF", 4);
  WRITE_U32 (headbuf + 4, size - 8);
  memcpy (headbuf + 8, "WAVE", 4);
  memcpy (headbuf + 12, "fmt ", 4);
  WRITE_U32 (headbuf + 16, 16);
  WRITE_U16 (headbuf + 20, 1);  /* format */
  WRITE_U16 (headbuf + 22, channels);
  WRITE_U32 (headbuf + 24, samplerate);
  WRITE_U32 (headbuf + 28, bytespersec);
  WRITE_U16 (headbuf + 32, align);
  WRITE_U16 (headbuf + 34, samplesize);
  memcpy (headbuf + 36, "data", 4);
  WRITE_U32 (headbuf + 40, size - 44);

  if (fwrite (headbuf, 1, 44, out) != 44)
    {
      printf ("ERROR: Failed to write wav header: %s\n", strerror (errno));
      return 1;
    }

  return 0;
}

static int
rewrite_header (FILE * out, unsigned int written)
{
  unsigned int length = written;

  length += 44;

  WRITE_U32 (headbuf + 4, length - 8);
  WRITE_U32 (headbuf + 40, length - 44);
  if (fseek (out, 0, SEEK_SET) != 0)
    {
      printf ("ERROR: Failed to seek on seekable file: %s\n",
          strerror (errno));
      return 1;
    }

  if (fwrite (headbuf, 1, 44, out) != 44)
    {
      printf ("ERROR: Failed to write wav header: %s\n", strerror (errno));
      return 1;
    }
  return 0;
}