Differences

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--- ffmpeg:av_read_frame [2007/11/22 16:56] – created deva
+++ ffmpeg:av_read_frame [2007/11/22 17:03] (current) – deva
@@ Line 1: / Line 1: @@
-=====avcodec_decode_video=====
+=====avc_read_frame=====
 ====Overview====
 Defined in ''avformat.h''\\
-Read a transport packet from a media file.\\
+Return the next frame of a stream.\\
-This function is obsolete and should never be used.\\
+The returned packet is valid until the next [[ffmpeg:av_read_frame()]] or until [[ffmpeg:av_close_input_file()]] and must be freed with [[ffmpeg:av_free_packet()]]. For video, the packet contains exactly one frame. For audio, it contains an integer number of frames if each frame has a known fixed size (e.g. PCM or ADPCM data). If the audio frames have a variable size (e.g. MPEG audio), then it contains one frame.\\
-Use [[ffmpeg:av_read_frame|av_read_frame()]] instead.
+''pkt->pts'', ''pkt->dts'' and ''pkt->duration'' are always set to correct values in ''AVStream.timebase'' units (and guessed if the format cannot provided them). ''pkt->pts'' can be ''AV_NOPTS_VALUE'' if the video format has B frames, so it is better to rely on ''pkt->dts'' if you do not decompress the payload.
 <code c>
-int av_read_packet(AVFormatContext *s,
+int av_read_frame(AVFormatContext *s,
-                   AVPacket *pkt);
+                  AVPacket *pkt);
 </code>
@@ Line 23: / Line 23: @@
 ====Return value====
-if OK. AVERROR_xxx if error.
+if OK, < 0 if error or end of file.
 ----
 Back to [[ffmpeg:ffmpeg]]