avcodec: add metadata to identify wrappers and hardware decoders

Explicitly identify decoder/encoder wrappers with a common name. This
saves API users from guessing by the name suffix. For example, they
don't have to guess that "h264_qsv" is the h264 QSV implementation, and
instead they can just check the AVCodec .codec and .wrapper_name fields.

Explicitly mark AVCodec entries that are hardware decoders or most
likely hardware decoders with new AV_CODEC_CAPs. The purpose is allowing
API users listing hardware decoders in a more generic way. The proposed
AVCodecHWConfig does not provide this information fully, because it's
concerned with decoder configuration, not information about the fact
whether the hardware is used or not.

AV_CODEC_CAP_HYBRID exists specifically for QSV, which can have software
implementations in case the hardware is not capable.

Based on a patch by Philip Langdale <philipl@overt.org>.

Merges Libav commit 47687a2f8aca3f65b6fdd117b1cb66a7409a7fd1.

1 files changed, 26 insertions, 0 deletions

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 5db6a81320..ce089b7c4a 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -1046,6 +1046,20 @@ typedef struct RcOverride{
 #define AV_CODEC_CAP_LOSSLESS         0x80000000
 
 /**
+ * Codec is backed by a hardware implementation. Typically used to
+ * identify a non-hwaccel hardware decoder. For information about hwaccels, use
+ * avcodec_get_hw_config() instead.
+ */
+#define AV_CODEC_CAP_HARDWARE            (1 << 18)
+
+/**
+ * Codec is potentially backed by a hardware implementation, but not
+ * necessarily. This is used instead of AV_CODEC_CAP_HARDWARE, if the
+ * implementation provides some sort of internal fallback.
+ */
+#define AV_CODEC_CAP_HYBRID              (1 << 19)
+
+/**
  * Pan Scan area.
  * This specifies the area which should be displayed.
  * Note there may be multiple such areas for one frame.
@@ -3377,6 +3391,18 @@ typedef struct AVCodec {
     const AVClass *priv_class;              ///< AVClass for the private context
     const AVProfile *profiles;              ///< array of recognized profiles, or NULL if unknown, array is terminated by {FF_PROFILE_UNKNOWN}
 
+    /**
+     * Group name of the codec implementation.
+     * This is a short symbolic name of the wrapper backing this codec. A
+     * wrapper uses some kind of external implementation for the codec, such
+     * as an external library, or a codec implementation provided by the OS or
+     * the hardware.
+     * If this field is NULL, this is a builtin, libavcodec native codec.
+     * If non-NULL, this will be the suffix in AVCodec.name in most cases
+     * (usually AVCodec.name will be of the form "<codec_name>_<wrapper_name>").
+     */
+    const char *wrapper_name;
+
     /*****************************************************************
      * No fields below this line are part of the public API. They
      * may not be used outside of libavcodec and can be changed and