29 строки
936 B
Plaintext
29 строки
936 B
Plaintext
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@TEMPLATE encoder_tmpl.c
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Forcing A Keyframe
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==================
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ INTRODUCTION
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This is an example demonstrating how to control placement of keyframes
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on a frame-by-frame basis.
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ INTRODUCTION
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Configuration
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-------------
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Keyframes can be forced by setting the VPX_EFLAG_FORCE_KF bit of the
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flags passed to `vpx_codec_control()`. In this example, we force a
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keyframe every 8 frames.
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PER_FRAME_CFG
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if(!(frame_cnt & 7))
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flags |= VPX_EFLAG_FORCE_KF;
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else
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flags &= ~VPX_EFLAG_FORCE_KF;
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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ PER_FRAME_CFG
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Observing The Effects
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---------------------
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The output of the encoder examples shows a 'K' rather than a dot '.'
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when the encoder generates a keyframe. Note that every 8 frames a 'K'
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is output.
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