bitwriter.c 1.06 KB
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/*
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 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
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 *
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 *  Use of this source code is governed by a BSD-style license
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 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
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 *  in the file PATENTS.  All contributing project authors may
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 *  be found in the AUTHORS file in the root of the source tree.
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 */

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#include <assert.h>
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#include "./bitwriter.h"
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void vpx_start_encode(vpx_writer *br, uint8_t *source) {
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  br->lowvalue = 0;
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  br->range = 255;
  br->count = -24;
  br->buffer = source;
  br->pos = 0;
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  vpx_write_bit(br, 0);
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}

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void vpx_stop_encode(vpx_writer *br) {
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  int i;
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#if CONFIG_BITSTREAM_DEBUG
  bitstream_queue_set_skip_write(1);
#endif  // CONFIG_BITSTREAM_DEBUG

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  for (i = 0; i < 32; i++) vpx_write_bit(br, 0);
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#if CONFIG_BITSTREAM_DEBUG
  bitstream_queue_set_skip_write(0);
#endif  // CONFIG_BITSTREAM_DEBUG

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  // Ensure there's no ambigous collision with any index marker bytes
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  if ((br->buffer[br->pos - 1] & 0xe0) == 0xc0) br->buffer[br->pos++] = 0;
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}