53 lines
1.2 KiB
C
53 lines
1.2 KiB
C
// Modifies the volume of an audio file
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#include <stdint.h>
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#include <stdio.h>
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#include <stdlib.h>
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// Number of bytes in .wav header
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const int HEADER_SIZE = 44;
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int main(int argc, char *argv[])
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{
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// Check command-line arguments
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if (argc != 4)
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{
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printf("Usage: ./volume input.wav output.wav factor\n");
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return 1;
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}
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// Open files and determine scaling factor
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FILE *input = fopen(argv[1], "r");
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if (input == NULL)
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{
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printf("Could not open file.\n");
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return 1;
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}
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FILE *output = fopen(argv[2], "w");
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if (output == NULL)
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{
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printf("Could not open file.\n");
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return 1;
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}
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float factor = atof(argv[3]);
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// TODO: Copy header from input file to output file
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uint8_t header[HEADER_SIZE];
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fread(header, HEADER_SIZE, 1, input);
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fwrite(header, HEADER_SIZE, 1, output);
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// TODO: Read samples from input file and write updated data to output file
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int16_t buffer;
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while (fread(&buffer, sizeof(int16_t), 1, input))
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{
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buffer *= factor;
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fwrite(&buffer, sizeof(int16_t), 1, output);
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}
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// Close files
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fclose(input);
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fclose(output);
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}
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