comparison src/opus-1.3/doc/trivial_example.c @ 69:7aeed7906520

Add Opus sources and macOS builds

+/* Copyright (c) 2013 Jean-Marc Valin */
+/*
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* This is meant to be a simple example of encoding and decoding audio
+   using Opus. It should make it easy to understand how the Opus API
+   works. For more information, see the full API documentation at:
+   https://www.opus-codec.org/docs/ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <opus.h>
+#include <stdio.h>
+
+/*The frame size is hardcoded for this sample code but it doesn't have to be*/
+#define FRAME_SIZE 960
+#define SAMPLE_RATE 48000
+#define CHANNELS 2
+#define APPLICATION OPUS_APPLICATION_AUDIO
+#define BITRATE 64000
+
+#define MAX_FRAME_SIZE 6*960
+#define MAX_PACKET_SIZE (3*1276)
+
+int main(int argc, char **argv)
+{
+   char *inFile;
+   FILE *fin;
+   char *outFile;
+   FILE *fout;
+   opus_int16 in[FRAME_SIZE*CHANNELS];
+   opus_int16 out[MAX_FRAME_SIZE*CHANNELS];
+   unsigned char cbits[MAX_PACKET_SIZE];
+   int nbBytes;
+   /*Holds the state of the encoder and decoder */
+   OpusEncoder *encoder;
+   OpusDecoder *decoder;
+   int err;
+
+   if (argc != 3)
+   {
+      fprintf(stderr, "usage: trivial_example input.pcm output.pcm\n");
+      fprintf(stderr, "input and output are 16-bit little-endian raw files\n");
+      return EXIT_FAILURE;
+   }
+
+   /*Create a new encoder state */
+   encoder = opus_encoder_create(SAMPLE_RATE, CHANNELS, APPLICATION, &err);
+   if (err<0)
+   {
+      fprintf(stderr, "failed to create an encoder: %s\n", opus_strerror(err));
+      return EXIT_FAILURE;
+   }
+   /* Set the desired bit-rate. You can also set other parameters if needed.
+      The Opus library is designed to have good defaults, so only set
+      parameters you know you need. Doing otherwise is likely to result
+      in worse quality, but better. */
+   err = opus_encoder_ctl(encoder, OPUS_SET_BITRATE(BITRATE));
+   if (err<0)
+   {
+      fprintf(stderr, "failed to set bitrate: %s\n", opus_strerror(err));
+      return EXIT_FAILURE;
+   }
+   inFile = argv[1];
+   fin = fopen(inFile, "r");
+   if (fin==NULL)
+   {
+      fprintf(stderr, "failed to open input file: %s\n", strerror(errno));
+      return EXIT_FAILURE;
+   }
+
+
+   /* Create a new decoder state. */
+   decoder = opus_decoder_create(SAMPLE_RATE, CHANNELS, &err);
+   if (err<0)
+   {
+      fprintf(stderr, "failed to create decoder: %s\n", opus_strerror(err));
+      return EXIT_FAILURE;
+   }
+   outFile = argv[2];
+   fout = fopen(outFile, "w");
+   if (fout==NULL)
+   {
+      fprintf(stderr, "failed to open output file: %s\n", strerror(errno));
+      return EXIT_FAILURE;
+   }
+
+   while (1)
+   {
+      int i;
+      unsigned char pcm_bytes[MAX_FRAME_SIZE*CHANNELS*2];
+      int frame_size;
+
+      /* Read a 16 bits/sample audio frame. */
+      fread(pcm_bytes, sizeof(short)*CHANNELS, FRAME_SIZE, fin);
+      if (feof(fin))
+         break;
+      /* Convert from little-endian ordering. */
+      for (i=0;i<CHANNELS*FRAME_SIZE;i++)
+         in[i]=pcm_bytes[2*i+1]<<8|pcm_bytes[2*i];
+
+      /* Encode the frame. */
+      nbBytes = opus_encode(encoder, in, FRAME_SIZE, cbits, MAX_PACKET_SIZE);
+      if (nbBytes<0)
+      {
+         fprintf(stderr, "encode failed: %s\n", opus_strerror(nbBytes));
+         return EXIT_FAILURE;
+      }
+
+
+      /* Decode the data. In this example, frame_size will be constant because
+         the encoder is using a constant frame size. However, that may not
+         be the case for all encoders, so the decoder must always check
+         the frame size returned. */
+      frame_size = opus_decode(decoder, cbits, nbBytes, out, MAX_FRAME_SIZE, 0);
+      if (frame_size<0)
+      {
+         fprintf(stderr, "decoder failed: %s\n", opus_strerror(frame_size));
+         return EXIT_FAILURE;
+      }
+
+      /* Convert to little-endian ordering. */
+      for(i=0;i<CHANNELS*frame_size;i++)
+      {
+         pcm_bytes[2*i]=out[i]&0xFF;
+         pcm_bytes[2*i+1]=(out[i]>>8)&0xFF;
+      }
+      /* Write the decoded audio to file. */
+      fwrite(pcm_bytes, sizeof(short), frame_size*CHANNELS, fout);
+   }
+   /*Destroy the encoder state*/
+   opus_encoder_destroy(encoder);
+   opus_decoder_destroy(decoder);
+   fclose(fin);
+   fclose(fout);
+   return EXIT_SUCCESS;
+}