=====avcodec_open=====
====Overview====
Defined in ''avcodec.h''\\

Initializes the AVCodecContext to use the given AVCodec. Prior to using this function the context has to be allocated.\\

The functions [[ffmpeg:avcodec_find_decoder_by_name()]], [[ffmpeg:avcodec_find_encoder_by_name()]], [[ffmpeg:avcodec_find_decoder()]] and [[ffmpeg:avcodec_find_encoder()]] provide an easy way for retrieving a codec.\\

WARNING: This function is not thread safe!\\

**Example:**
<code c>
avcodec_register_all();

codec = avcodec_find_decoder(CODEC_ID_H264);
if (!codec) exit(1);

context = avcodec_alloc_context();
if (avcodec_open(context, codec) < 0) exit(1);
</code>

<code c>
int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
</code>

====Parameters====
===avctx===
<code c>AVCodecContext *avctx</code>
The [[ffmpeg:AVCodecContext]] which will be set up to use the given codec.

===codec===
<code c>AVCodec *codec</code>
The [[ffmpeg:AVCodec]] to use within the context.

====Return value====
Zero on success, a negative value on error

====See also====
[[ffmpeg:avcodec_alloc_context()]], [[ffmpeg:avcodec_find_decoder()]], [[ffmpeg:avcodec_find_encoder()]]

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Back to [[ffmpeg:ffmpeg]]