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-rw-r--r--audio_read.c460
1 files changed, 460 insertions, 0 deletions
diff --git a/audio_read.c b/audio_read.c
new file mode 100644
index 0000000..6c6050d
--- /dev/null
+++ b/audio_read.c
@@ -0,0 +1,460 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "common.h"
+#include "encoder.h"
+#include "options.h"
+#include "portableio.h"
+#include "audio_read.h"
+
+
+/************************************************************************
+*
+* read_samples()
+*
+* PURPOSE: reads the PCM samples from a file to the buffer
+*
+* SEMANTICS:
+* Reads #samples_read# number of shorts from #musicin# filepointer
+* into #sample_buffer[]#. Returns the number of samples read.
+*
+************************************************************************/
+
+unsigned long
+read_samples (FILE * musicin, short sample_buffer[2304],
+ unsigned long num_samples, unsigned long frame_size)
+{
+ unsigned long samples_read;
+ static unsigned long samples_to_read;
+ static char init = TRUE;
+
+ if (init) {
+ samples_to_read = num_samples;
+ init = FALSE;
+ }
+ if (samples_to_read >= frame_size)
+ samples_read = frame_size;
+ else
+ samples_read = samples_to_read;
+ if ((samples_read =
+ fread (sample_buffer, sizeof (short), (int) samples_read,
+ musicin)) == 0)
+ fprintf (stderr, "Hit end of audio data\n");
+ /*
+ Samples are big-endian. If this is a little-endian machine
+ we must swap
+ */
+ if (NativeByteOrder == order_unknown) {
+ NativeByteOrder = DetermineByteOrder ();
+ if (NativeByteOrder == order_unknown) {
+ fprintf (stderr, "byte order not determined\n");
+ exit (1);
+ }
+ }
+ if (NativeByteOrder != order_littleEndian || (glopts.byteswap == TRUE))
+ SwapBytesInWords (sample_buffer, samples_read);
+
+ if (num_samples != MAX_U_32_NUM)
+ samples_to_read -= samples_read;
+
+ if (samples_read < frame_size && samples_read > 0) {
+ /* fill out frame with zeros */
+ for (; samples_read < frame_size; sample_buffer[samples_read++] = 0);
+ samples_to_read = 0;
+ samples_read = frame_size;
+ }
+ return (samples_read);
+}
+
+/************************************************************************
+*
+* get_audio()
+*
+* PURPOSE: reads a frame of audio data from a file to the buffer,
+* aligns the data for future processing, and separates the
+* left and right channels
+*
+*
+************************************************************************/
+unsigned long
+get_audio (FILE * musicin, short buffer[2][1152], unsigned long num_samples,
+ int nch, frame_header *header)
+{
+ int j;
+ short insamp[2304];
+ unsigned long samples_read;
+
+ if (nch == 2) { /* stereo */
+ samples_read =
+ read_samples (musicin, insamp, num_samples, (unsigned long) 2304);
+ if (glopts.channelswap == TRUE) {
+ for (j = 0; j < 1152; j++) {
+ buffer[1][j] = insamp[2 * j];
+ buffer[0][j] = insamp[2 * j + 1];
+ }
+ } else {
+ for (j = 0; j < 1152; j++) {
+ buffer[0][j] = insamp[2 * j];
+ buffer[1][j] = insamp[2 * j + 1];
+ }
+ }
+ } else if (glopts.downmix == TRUE) {
+ samples_read =
+ read_samples (musicin, insamp, num_samples, (unsigned long) 2304);
+ for (j = 0; j < 1152; j++) {
+ buffer[0][j] = 0.5 * (insamp[2 * j] + insamp[2 * j + 1]);
+ }
+ } else { /* mono */
+ samples_read =
+ read_samples (musicin, insamp, num_samples, (unsigned long) 1152);
+ for (j = 0; j < 1152; j++) {
+ buffer[0][j] = insamp[j];
+ /* buffer[1][j] = 0; don't bother zeroing this buffer. MFC Nov 99 */
+ }
+ }
+ return (samples_read);
+}
+
+
+/*****************************************************************************
+*
+* Routines to determine byte order and swap bytes
+*
+*****************************************************************************/
+
+enum byte_order DetermineByteOrder (void)
+{
+ char s[sizeof (long) + 1];
+ union {
+ long longval;
+ char charval[sizeof (long)];
+ } probe;
+ probe.longval = 0x41424344L; /* ABCD in ASCII */
+ strncpy (s, probe.charval, sizeof (long));
+ s[sizeof (long)] = '\0';
+ /* fprintf( stderr, "byte order is %s\n", s ); */
+ if (strcmp (s, "ABCD") == 0)
+ return order_bigEndian;
+ else if (strcmp (s, "DCBA") == 0)
+ return order_littleEndian;
+ else
+ return order_unknown;
+}
+
+void SwapBytesInWords (short *loc, int words)
+{
+ int i;
+ short thisval;
+ char *dst, *src;
+ src = (char *) &thisval;
+ for (i = 0; i < words; i++) {
+ thisval = *loc;
+ dst = (char *) loc++;
+ dst[0] = src[1];
+ dst[1] = src[0];
+ }
+}
+
+/*****************************************************************************
+ *
+ * Read Audio Interchange File Format (AIFF) headers.
+ *
+ *****************************************************************************/
+
+int aiff_read_headers (FILE * file_ptr, IFF_AIFF * aiff_ptr)
+{
+ int chunkSize, subSize, sound_position;
+
+ if (fseek (file_ptr, 0, SEEK_SET) != 0)
+ return -1;
+
+ if (Read32BitsHighLow (file_ptr) != IFF_ID_FORM)
+ return -1;
+
+ chunkSize = Read32BitsHighLow (file_ptr);
+
+ if (Read32BitsHighLow (file_ptr) != IFF_ID_AIFF)
+ return -1;
+
+ sound_position = 0;
+ while (chunkSize > 0) {
+ chunkSize -= 4;
+ switch (Read32BitsHighLow (file_ptr)) {
+
+ case IFF_ID_COMM:
+ chunkSize -= subSize = Read32BitsHighLow (file_ptr);
+ aiff_ptr->numChannels = Read16BitsHighLow (file_ptr);
+ subSize -= 2;
+ aiff_ptr->numSampleFrames = Read32BitsHighLow (file_ptr);
+ subSize -= 4;
+ aiff_ptr->sampleSize = Read16BitsHighLow (file_ptr);
+ subSize -= 2;
+ aiff_ptr->sampleRate = ReadIeeeExtendedHighLow (file_ptr);
+ subSize -= 10;
+ while (subSize > 0) {
+ getc (file_ptr);
+ subSize -= 1;
+ }
+ break;
+
+ case IFF_ID_SSND:
+ chunkSize -= subSize = Read32BitsHighLow (file_ptr);
+ aiff_ptr->blkAlgn.offset = Read32BitsHighLow (file_ptr);
+ subSize -= 4;
+ aiff_ptr->blkAlgn.blockSize = Read32BitsHighLow (file_ptr);
+ subSize -= 4;
+ sound_position = ftell (file_ptr) + aiff_ptr->blkAlgn.offset;
+ if (fseek (file_ptr, (long) subSize, SEEK_CUR) != 0)
+ return -1;
+ aiff_ptr->sampleType = IFF_ID_SSND;
+ break;
+
+ default:
+ chunkSize -= subSize = Read32BitsHighLow (file_ptr);
+ while (subSize > 0) {
+ getc (file_ptr);
+ subSize -= 1;
+ }
+ break;
+ }
+ }
+ return sound_position;
+}
+
+/*****************************************************************************
+ *
+ * Seek past some Audio Interchange File Format (AIFF) headers to sound data.
+ *
+ *****************************************************************************/
+
+int aiff_seek_to_sound_data (FILE * file_ptr)
+{
+ if (fseek
+ (file_ptr, AIFF_FORM_HEADER_SIZE + AIFF_SSND_HEADER_SIZE,
+ SEEK_SET) != 0)
+ return (-1);
+ return (0);
+}
+
+/************************************************************
+* parse_input_file()
+* Determine the type of sound file. (stdin, wav, aiff, raw pcm)
+* Determine Sampling Frequency
+* number of samples
+* whether the new sample is stereo or mono.
+*
+* If file is coming from /dev/stdin assume it is raw PCM. (it's what I use. YMMV)
+*
+* This is just a hacked together function. The aiff parsing comes from the ISO code.
+* The WAV code comes from Nick Burch
+* The ugly /dev/stdin hack comes from me.
+* MFC Dec 99
+**************************************************************/
+void
+parse_input_file (FILE * musicin, char inPath[MAX_NAME_SIZE], frame_header *header,
+ unsigned long *num_samples)
+{
+
+ IFF_AIFF pcm_aiff_data;
+ long soundPosition;
+
+ unsigned char wave_header_buffer[40]; //HH fixed
+ int wave_header_read = 0;
+ int wave_header_stereo = -1;
+ int wave_header_16bit = -1;
+ unsigned long samplerate;
+
+ /*************************** STDIN ********************************/
+ /* check if we're reading from stdin. Assume it's a raw PCM file. */
+ /* Of course, you could be piping a WAV file into stdin. Not done in this code */
+ /* this code is probably very dodgy and was written to suit my needs. MFC Dec 99 */
+ if ((strcmp (inPath, "/dev/stdin") == 0)) {
+ fprintf (stderr, "Reading from stdin\n");
+ fprintf (stderr, "Remember to set samplerate with '-s'.\n");
+ *num_samples = MAX_U_32_NUM; /* huge sound file */
+ return;
+ }
+
+ /**************************** AIFF ********************************/
+ if ((soundPosition = aiff_read_headers (musicin, &pcm_aiff_data)) != -1) {
+ fprintf (stderr, ">>> Using Audio IFF sound file headers\n");
+ aiff_check (inPath, &pcm_aiff_data, &header->version);
+ if (fseek (musicin, soundPosition, SEEK_SET) != 0) {
+ fprintf (stderr, "Could not seek to PCM sound data in \"%s\".\n",
+ inPath);
+ exit (1);
+ }
+ fprintf (stderr, "Parsing AIFF audio file \n");
+ header->sampling_frequency =
+ SmpFrqIndex ((long) pcm_aiff_data.sampleRate, &header->version);
+ fprintf (stderr, ">>> %f Hz sampling frequency selected\n",
+ pcm_aiff_data.sampleRate);
+
+ /* Determine number of samples in sound file */
+ *num_samples = pcm_aiff_data.numChannels * pcm_aiff_data.numSampleFrames;
+
+ if (pcm_aiff_data.numChannels == 1) {
+ header->mode = MPG_MD_MONO;
+ header->mode_ext = 0;
+ }
+ return;
+ }
+
+ /**************************** WAVE *********************************/
+ /* Nick Burch <The_Leveller@newmail.net> */
+ /*********************************/
+ /* Wave File Headers: (Dec) */
+ /* 8-11 = "WAVE" */
+ /* 22 = Stereo / Mono */
+ /* 01 = mono, 02 = stereo */
+ /* 24 = Sampling Frequency */
+ /* 32 = Data Rate */
+ /* 01 = x1 (8bit Mono) */
+ /* 02 = x2 (8bit Stereo or */
+ /* 16bit Mono) */
+ /* 04 = x4 (16bit Stereo) */
+ /*********************************/
+
+ fseek (musicin, 0, SEEK_SET);
+ fread (wave_header_buffer, 1, 40, musicin);
+
+ if (wave_header_buffer[8] == 'W' && wave_header_buffer[9] == 'A'
+ && wave_header_buffer[10] == 'V' && wave_header_buffer[11] == 'E') {
+ fprintf (stderr, "Parsing Wave File Header\n");
+ if (NativeByteOrder == order_unknown) {
+ NativeByteOrder = DetermineByteOrder ();
+ if (NativeByteOrder == order_unknown) {
+ fprintf (stderr, "byte order not determined\n");
+ exit (1);
+ }
+ }
+ if (NativeByteOrder == order_littleEndian) {
+ samplerate = *(unsigned long *) (&wave_header_buffer[24]);
+ } else {
+ samplerate = wave_header_buffer[27] +
+ (wave_header_buffer[26] << 8) +
+ (wave_header_buffer[25] << 16) + (wave_header_buffer[24] << 24);
+ }
+ /* Wave File */
+ wave_header_read = 1;
+ switch (samplerate) {
+ case 44100:
+ case 48000:
+ case 32000:
+ case 24000:
+ case 22050:
+ case 16000:
+ fprintf (stderr, ">>> %ld Hz sampling freq selected\n", samplerate);
+ break;
+ default:
+ /* Unknown Unsupported Frequency */
+ fprintf (stderr, ">>> Unknown samp freq %ld Hz in Wave Header\n",
+ samplerate);
+ fprintf (stderr, ">>> Default 44.1 kHz samp freq selected\n");
+ samplerate = 44100;
+ }
+
+ if ((header->sampling_frequency =
+ SmpFrqIndex ((long) samplerate, &header->version)) < 0) {
+ fprintf (stderr, "invalid sample rate\n");
+ exit (0);
+ }
+
+ if ((long) wave_header_buffer[22] == 1) {
+ fprintf (stderr, ">>> Input Wave File is Mono\n");
+ wave_header_stereo = 0;
+ header->mode = MPG_MD_MONO;
+ header->mode_ext = 0;
+ }
+ if ((long) wave_header_buffer[22] == 2) {
+ fprintf (stderr, ">>> Input Wave File is Stereo\n");
+ wave_header_stereo = 1;
+ }
+ if ((long) wave_header_buffer[32] == 1) {
+ fprintf (stderr, ">>> Input Wave File is 8 Bit\n");
+ wave_header_16bit = 0;
+ fprintf (stderr, "Input File must be 16 Bit! Please Re-sample");
+ exit (1);
+ }
+ if ((long) wave_header_buffer[32] == 2) {
+ if (wave_header_stereo == 1) {
+ fprintf (stderr, ">>> Input Wave File is 8 Bit\n");
+ wave_header_16bit = 0;
+ fprintf (stderr, "Input File must be 16 Bit! Please Re-sample");
+ exit (1);
+ } else {
+ /* fprintf(stderr, ">>> Input Wave File is 16 Bit\n" ); */
+ wave_header_16bit = 1;
+ }
+ }
+ if ((long) wave_header_buffer[32] == 4) {
+ /* fprintf(stderr, ">>> Input Wave File is 16 Bit\n" ); */
+ wave_header_16bit = 1;
+ }
+ /* should probably use the wave header to determine size here FIXME MFC Feb 2003 */
+ *num_samples = MAX_U_32_NUM;
+ if (fseek (musicin, 44, SEEK_SET) != 0) { /* there's a way of calculating the size of the
+ wave header. i'll just jump 44 to start with */
+ fprintf (stderr, "Could not seek to PCM sound data in \"%s\".\n",
+ inPath);
+ exit (1);
+ }
+ return;
+ }
+
+ /*************************** PCM **************************/
+ fprintf (stderr, "No header found. Assuming Raw PCM sound file\n");
+ /* Raw PCM. No header. Reset the input file to read from the start */
+ fseek (musicin, 0, SEEK_SET);
+ /* Assume it is a huge sound file since there's no real info available */
+ /* FIXME: Could always fstat the file? Probably not worth it. MFC Feb 2003 */
+ *num_samples = MAX_U_32_NUM;
+}
+
+
+
+/************************************************************************
+*
+* aiff_check
+*
+* PURPOSE: Checks AIFF header information to make sure it is valid.
+* Exits if not.
+*
+************************************************************************/
+
+void aiff_check (char *file_name, IFF_AIFF * pcm_aiff_data, int *version)
+{
+ if (pcm_aiff_data->sampleType != IFF_ID_SSND) {
+ fprintf (stderr, "Sound data is not PCM in \"%s\".\n", file_name);
+ exit (1);
+ }
+
+ if (SmpFrqIndex ((long) pcm_aiff_data->sampleRate, version) < 0) {
+ fprintf (stderr, "in \"%s\".\n", file_name);
+ exit (1);
+ }
+
+ if (pcm_aiff_data->sampleSize != sizeof (short) * BITS_IN_A_BYTE) {
+ fprintf (stderr, "Sound data is not %d bits in \"%s\".\n",
+ sizeof (short) * BITS_IN_A_BYTE, file_name);
+ exit (1);
+ }
+
+ if (pcm_aiff_data->numChannels != MONO
+ && pcm_aiff_data->numChannels != STEREO) {
+ fprintf (stderr, "Sound data is not mono or stereo in \"%s\".\n",
+ file_name);
+ exit (1);
+ }
+
+ if (pcm_aiff_data->blkAlgn.blockSize != 0) {
+ fprintf (stderr, "Block size is not %d bytes in \"%s\".\n", 0, file_name);
+ exit (1);
+ }
+
+ if (pcm_aiff_data->blkAlgn.offset != 0) {
+ fprintf (stderr, "Block offset is not %d bytes in \"%s\".\n", 0,
+ file_name);
+ exit (1);
+ }
+}
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