我怎样才能知道ffmpeg错误代码的含义?

I'm using the function avcodec_decode_video2. On an encoding change in the stream, it returns -1094995529. The documentation only states:

我使用的是avcodec_decode_video2函数。在流的编码更改中，它返回-1094995529。文档只状态:

On error a negative value is returned, otherwise the number of bytes used or zero if no frame could be decompressed.

在错误中返回一个负值，否则，如果没有任何帧可以被解压，则使用的字节数或为零。

But there doesn't seem to be an enum of return codes or any other form of documentation. What does the error mean and how can I determine that in general?

但似乎没有一个返回代码或任何其他形式的文档。这个误差是什么意思，我又如何确定它的一般意义?

2 个解决方案

#1

Error codes from ffmpeg (error.h from avutil) : http://ffmpeg.org/doxygen/trunk/error_8h_source.html

错误代码从ffmpeg(错误)。h来自avutil): http://ffmpeg.org/doxygen/trunk/error_8h_source.html。

It turns out the value you specified is :

你所指定的值是:

#define AVERROR_INVALIDDATA        FFERRTAG( 'I','N','D','A')

The -1094995529 becomes -0x41444E49 and when you look at those letters, in ACSII, 0x41 = 'A', 0x44 = 'D', 0x4E = 'N, and 0x49 = 'I'. Due to the macro/etc things are reversed, so ADNI becomes INDA, which you can see from the #define snippet, is the AVERROR_INVALIDDATA defined FFERRTAG( 'I','N','D','A').

-1094995529变成-0x41444E49，当你查看这些字母时，在ACSII中，0x41 = 'A'， 0x44 = 'D'， 0x4E = 'N，和0x49 = 'I'。由于宏/等的原因，所以ADNI变成了INDA，从#define代码片段中可以看到，是AVERROR_INVALIDDATA定义的FFERRTAG('I'，'N'，'D'，'A')。

The rest of the error codes are in that file and I've pasted them below here :

其余的错误代码都在这个文件中我在下面粘贴了

#define AVERROR_BSF_NOT_FOUND      FFERRTAG(0xF8,'B','S','F') ///< Bitstream filter not found
#define AVERROR_BUG                FFERRTAG( 'B','U','G','!') ///< Internal bug, also see AVERROR_BUG2
#define AVERROR_BUFFER_TOO_SMALL   FFERRTAG( 'B','U','F','S') ///< Buffer too small
#define AVERROR_DECODER_NOT_FOUND  FFERRTAG(0xF8,'D','E','C') ///< Decoder not found
#define AVERROR_DEMUXER_NOT_FOUND  FFERRTAG(0xF8,'D','E','M') ///< Demuxer not found
#define AVERROR_ENCODER_NOT_FOUND  FFERRTAG(0xF8,'E','N','C') ///< Encoder not found
#define AVERROR_EOF                FFERRTAG( 'E','O','F',' ') ///< End of file
#define AVERROR_EXIT               FFERRTAG( 'E','X','I','T') ///< Immediate exit was requested; the called function should not be restarted
#define AVERROR_EXTERNAL           FFERRTAG( 'E','X','T',' ') ///< Generic error in an external library
#define AVERROR_FILTER_NOT_FOUND   FFERRTAG(0xF8,'F','I','L') ///< Filter not found
#define AVERROR_INVALIDDATA        FFERRTAG( 'I','N','D','A') ///< Invalid data found when processing input
#define AVERROR_MUXER_NOT_FOUND    FFERRTAG(0xF8,'M','U','X') ///< Muxer not found
#define AVERROR_OPTION_NOT_FOUND   FFERRTAG(0xF8,'O','P','T') ///< Option not found
#define AVERROR_PATCHWELCOME       FFERRTAG( 'P','A','W','E') ///< Not yet implemented in FFmpeg, patches welcome
#define AVERROR_PROTOCOL_NOT_FOUND FFERRTAG(0xF8,'P','R','O') ///< Protocol not found
#define AVERROR_STREAM_NOT_FOUND   FFERRTAG(0xF8,'S','T','R') ///< Stream not found
#define AVERROR_BUG2               FFERRTAG( 'B','U','G',' ')
#define AVERROR_UNKNOWN            FFERRTAG( 'U','N','K','N') ///< Unknown error, typically from an external library
#define AVERROR_EXPERIMENTAL       (-0x2bb2afa8) ///< Requested feature is flagged experimental. Set strict_std_compliance if you really want to use it.
#define AVERROR_INPUT_CHANGED      (-0x636e6701) ///< Input changed between calls. Reconfiguration is required. (can be OR-ed with AVERROR_OUTPUT_CHANGED)
#define AVERROR_OUTPUT_CHANGED     (-0x636e6702) ///< Output changed between calls. Reconfiguration is required. (can be OR-ed with AVERROR_INPUT_CHANGED)
#define AVERROR_HTTP_BAD_REQUEST   FFERRTAG(0xF8,'4','0','0')
#define AVERROR_HTTP_UNAUTHORIZED  FFERRTAG(0xF8,'4','0','1')
#define AVERROR_HTTP_FORBIDDEN     FFERRTAG(0xF8,'4','0','3')
#define AVERROR_HTTP_NOT_FOUND     FFERRTAG(0xF8,'4','0','4')
#define AVERROR_HTTP_OTHER_4XX     FFERRTAG(0xF8,'4','X','X')
#define AVERROR_HTTP_SERVER_ERROR  FFERRTAG(0xF8,'5','X','X')

#2

Errors mentioned are POSIX related:

所提到的错误与POSIX有关:

in file libavcodec\avcodec.h

在文件libavcodec \ avcodec.h

#include <errno.h>

#if EINVAL > 0
#define AVERROR(e) (-(e)) /**< Returns a negative error code from a POSIX error code, to return from library functions. */
#define AVUNERROR(e) (-(e)) /**< Returns a POSIX error code from a library function error return value. */
#else
/* Some platforms have E* and errno already negated. */
#define AVERROR(e) (e)
#define AVUNERROR(e) (e)
#endif
#define AVERROR_UNKNOWN     AVERROR(EINVAL)  /**< unknown error */
#define AVERROR_IO          AVERROR(EIO)     /**< I/O error */
#define AVERROR_NUMEXPECTED AVERROR(EDOM)    /**< Number syntax expected in filename. */
#define AVERROR_INVALIDDATA AVERROR(EINVAL)  /**< invalid data found */
#define AVERROR_NOMEM       AVERROR(ENOMEM)  /**< not enough memory */
#define AVERROR_NOFMT       AVERROR(EILSEQ)  /**< unknown format */
#define AVERROR_NOTSUPP     AVERROR(ENOSYS)  /**< Operation not supported. */
#define AVERROR_NOENT       AVERROR(ENOENT)  /**< No such file or directory. */
#define AVERROR_EOF         AVERROR(EPIPE)   /**< End of file. */
#define AVERROR_PATCHWELCOME    -MKTAG('P','A','W','E') /**< Not yet implemented in FFmpeg. Patches welcome. */

This is full set of Errors you can meet. Simply inside your code check return value against all of them.

这是你能遇到的全部错误。简单地在代码中检查返回值。

#1