@@ -15,6 +15,9 @@ libavutil:     2015-08-28

 API changes, most recent first:

+2017-09-27 - xxxxxxx - lavu 55.77.100 / lavu 55.31.0 - cpu.h

+  Add av_cpu_max_align() for querying maximum required data alignment.

+

 2017-09-26 - xxxxxxx - lavc 57.106.102 - avcodec.h

   Deprecate AVCodecContext.refcounted_frames. This was useful for deprecated

   API only (avcodec_decode_video2/avcodec_decode_audio4). The new decode APIs

@@ -16,9 +16,11 @@

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  */

+#include <stddef.h>

 #include <stdint.h>

 #include <stdatomic.h>

+#include "attributes.h"

 #include "cpu.h"

 #include "cpu_internal.h"

 #include "config.h"

@@ -299,3 +301,40 @@ int av_cpu_count(void)

     return nb_cpus;

 }

+

+size_t av_cpu_max_align(void)

+{

+    int av_unused flags = av_get_cpu_flags();

+

+#if ARCH_ARM || ARCH_AARCH64

+    if (flags & AV_CPU_FLAG_NEON)

+        return 16;

+#elif ARCH_PPC

+    if (flags & (AV_CPU_FLAG_ALTIVEC   |

+                 AV_CPU_FLAG_VSX       |

+                 AV_CPU_FLAG_POWER8))

+        return 16;

+#elif ARCH_X86

+    if (flags & (AV_CPU_FLAG_AVX2      |

+                 AV_CPU_FLAG_AVX       |

+                 AV_CPU_FLAG_XOP       |

+                 AV_CPU_FLAG_FMA4      |

+                 AV_CPU_FLAG_FMA3      |

+                 AV_CPU_FLAG_AVXSLOW))

+        return 32;

+    if (flags & (AV_CPU_FLAG_AESNI     |

+                 AV_CPU_FLAG_SSE42     |

+                 AV_CPU_FLAG_SSE4      |

+                 AV_CPU_FLAG_SSSE3     |

+                 AV_CPU_FLAG_SSE3      |

+                 AV_CPU_FLAG_SSE2      |

+                 AV_CPU_FLAG_SSE       |

+                 AV_CPU_FLAG_ATOM      |

+                 AV_CPU_FLAG_SSSE3SLOW |

+                 AV_CPU_FLAG_SSE3SLOW  |

+                 AV_CPU_FLAG_SSE2SLOW))

+        return 16;

+#endif

+

+    return 8;

+}

@@ -21,6 +21,8 @@

 #ifndef AVUTIL_CPU_H

 #define AVUTIL_CPU_H

+#include <stddef.h>

+

 #include "attributes.h"

 #define AV_CPU_FLAG_FORCE    0x80000000 /* force usage of selected flags (OR) */

@@ -113,4 +115,15 @@ int av_parse_cpu_caps(unsigned *flags, const char *s);

  */

 int av_cpu_count(void);

+/**

+ * Get the maximum data alignment that may be required by FFmpeg.

+ *

+ * Note that this is affected by the build configuration and the CPU flags mask,

+ * so e.g. if the CPU supports AVX, but libavutil has been built with

+ * --disable-avx or the AV_CPU_FLAG_AVX flag has been disabled through

+ *  av_set_cpu_flags_mask(), then this function will behave as if AVX is not

+ *  present.

+ */

+size_t av_cpu_max_align(void);

+

 #endif /* AVUTIL_CPU_H */

@@ -80,7 +80,7 @@

 #define LIBAVUTIL_VERSION_MAJOR  55

-#define LIBAVUTIL_VERSION_MINOR  76

+#define LIBAVUTIL_VERSION_MINOR  77

 #define LIBAVUTIL_VERSION_MICRO 100

 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \