lavc: introduce avcodec_open2() as a replacement for avcodec_open().

Adds support for decoder-private options and makes setting other options
simpler.

4 files changed, 66 insertions, 2 deletions

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index b26bac7bef..ba0c636292 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -30,6 +30,7 @@
 #include "libavutil/samplefmt.h"
 #include "libavutil/avutil.h"
 #include "libavutil/cpu.h"
+#include "libavutil/dict.h"
 #include "libavutil/log.h"
 #include "libavutil/pixfmt.h"
 #include "libavutil/rational.h"
@@ -3619,6 +3620,7 @@ int avcodec_default_execute(AVCodecContext *c, int (*func)(AVCodecContext *c2, v
 int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2, void *arg2, int, int),void *arg, int *ret, int count);
 //FIXME func typedef
 
+#if FF_API_AVCODEC_OPEN
 /**
  * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
  * function the context has to be allocated.
@@ -3645,8 +3647,45 @@ int avcodec_default_execute2(AVCodecContext *c, int (*func)(AVCodecContext *c2,
  * @param codec The codec to use within the context.
  * @return zero on success, a negative value on error
  * @see avcodec_alloc_context, avcodec_find_decoder, avcodec_find_encoder, avcodec_close
+ *
+ * @deprecated use avcodec_open2
  */
+attribute_deprecated
 int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
+#endif
+
+/**
+ * Initialize the AVCodecContext to use the given AVCodec. Prior to using this
+ * function the context has to be allocated with avcodec_alloc_context().
+ *
+ * The functions avcodec_find_decoder_by_name(), avcodec_find_encoder_by_name(),
+ * avcodec_find_decoder() and avcodec_find_encoder() provide an easy way for
+ * retrieving a codec.
+ *
+ * @warning This function is not thread safe!
+ *
+ * @code
+ * avcodec_register_all();
+ * av_dict_set(&opts, "b", "2.5M", 0);
+ * codec = avcodec_find_decoder(CODEC_ID_H264);
+ * if (!codec)
+ *     exit(1);
+ *
+ * context = avcodec_alloc_context();
+ *
+ * if (avcodec_open(context, codec, opts) < 0)
+ *     exit(1);
+ * @endcode
+ *
+ * @param avctx The context to initialize.
+ * @param options A dictionary filled with AVCodecContext and codec-private options.
+ *                On return this object will be filled with options that were not found.
+ *
+ * @return zero on success, a negative value on error
+ * @see avcodec_alloc_context3(), avcodec_find_decoder(), avcodec_find_encoder(),
+ *      av_dict_set(), av_opt_find().
+ */
+int avcodec_open2(AVCodecContext *avctx, AVCodec *codec, AVDictionary **options);
 
 /**
  * Decode the audio frame of size avpkt->size from avpkt->data into samples.
diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c
index 73bcc5b229..f298993c0c 100644
--- a/libavcodec/mpegvideo_enc.c
+++ b/libavcodec/mpegvideo_enc.c
@@ -973,7 +973,7 @@ static int estimate_best_b_count(MpegEncContext *s){
     c->time_base= s->avctx->time_base;
     c->max_b_frames= s->max_b_frames;
 
-    if (avcodec_open(c, codec) < 0)
+    if (avcodec_open2(c, codec, NULL) < 0)
         return -1;
 
     for(i=0; i<s->max_b_frames+2; i++){
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 722f758231..5ad0c51d02 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -32,6 +32,7 @@
 #include "libavutil/audioconvert.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/samplefmt.h"
+#include "libavutil/dict.h"
 #include "avcodec.h"
 #include "dsputil.h"
 #include "libavutil/opt.h"
@@ -467,9 +468,20 @@ AVFrame *avcodec_alloc_frame(void){
     return pic;
 }
 
+#if FF_API_AVCODEC_OPEN
 int attribute_align_arg avcodec_open(AVCodecContext *avctx, AVCodec *codec)
 {
+    return avcodec_open2(avctx, codec, NULL);
+}
+#endif
+
+int attribute_align_arg avcodec_open2(AVCodecContext *avctx, AVCodec *codec, AVDictionary **options)
+{
     int ret = 0;
+    AVDictionary *tmp = NULL;
+
+    if (options)
+        av_dict_copy(&tmp, *options, 0);
 
     /* If there is a user-supplied mutex locking routine, call it. */
     if (ff_lockmgr_cb) {
@@ -496,14 +508,18 @@ int attribute_align_arg avcodec_open(AVCodecContext *avctx, AVCodec *codec)
             ret = AVERROR(ENOMEM);
             goto end;
         }
-        if(codec->priv_class){ //this can be droped once all user apps use   avcodec_get_context_defaults3()
+        if (codec->priv_class) {
             *(AVClass**)avctx->priv_data= codec->priv_class;
             av_opt_set_defaults(avctx->priv_data);
         }
       }
+      if (codec->priv_class && (ret = av_opt_set_dict(avctx->priv_data, &tmp) < 0))
+          goto free_and_end;
     } else {
         avctx->priv_data = NULL;
     }
+    if ((ret = av_opt_set_dict(avctx, &tmp)) < 0)
+        goto free_and_end;
 
     if(avctx->coded_width && avctx->coded_height)
         avcodec_set_dimensions(avctx, avctx->coded_width, avctx->coded_height);
@@ -615,8 +631,14 @@ end:
     if (ff_lockmgr_cb) {
         (*ff_lockmgr_cb)(&codec_mutex, AV_LOCK_RELEASE);
     }
+    if (options) {
+        av_dict_free(options);
+        *options = tmp;
+    }
+
     return ret;
 free_and_end:
+    av_dict_free(&tmp);
     av_freep(&avctx->priv_data);
     avctx->codec= NULL;
     goto end;
diff --git a/libavcodec/version.h b/libavcodec/version.h
index aded68e83e..f4a0ecd868 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -68,5 +68,8 @@
 #ifndef FF_API_GET_PIX_FMT_NAME
 #define FF_API_GET_PIX_FMT_NAME (LIBAVCODEC_VERSION_MAJOR < 54)
 #endif
+#ifndef FF_API_AVCODEC_OPEN
+#define FF_API_AVCODEC_OPEN     (LIBAVCODEC_VERSION_MAJOR < 54)
+#endif
 
 #endif /* AVCODEC_VERSION_H */