Merge commit 'a8068346'

* commit 'a8068346':
  lavc: add a variant of av_get_audio_frame_duration working with AVCodecParameters

Fixes from jamrial incorporated.
Merged-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

doc/APIchanges

@@ -17,6 +17,7 @@ API changes, most recent first:
 
 2016-xx-xx - lavc 57.33.0 - avcodec.h
   xxxxxxx - Add AVCodecParameters and its related API.
+  xxxxxxx - Add av_get_audio_frame_duration2().
 
 2016-03-11 - xxxxxxx - lavf/lavc 57.28.101
   Add requirement to bitstream filtering API that returned packets with

libavcodec/avcodec.h

@@ -5342,6 +5342,12 @@ int av_get_exact_bits_per_sample(enum AVCodecID codec_id);
  */
 int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes);
 
+/**
+ * This function is the same as av_get_audio_frame_duration(), except it works
+ * with AVCodecParameters instead of an AVCodecContext.
+ */
+int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes);
+
 
 typedef struct AVBitStreamFilterContext {
     void *priv_data;

libavcodec/utils.c

@@ -3145,21 +3145,16 @@ int av_get_bits_per_sample(enum AVCodecID codec_id)
     }
 }
 
-int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
+static int get_audio_frame_duration(enum AVCodecID id, int sr, int ch, int ba,
+                                    uint32_t tag, int bits_per_coded_sample, int64_t bitrate,
+                                    uint8_t * extradata, int frame_size, int frame_bytes)
 {
-    int id, sr, ch, ba, tag, bps;
-
-    id  = avctx->codec_id;
-    sr  = avctx->sample_rate;
-    ch  = avctx->channels;
-    ba  = avctx->block_align;
-    tag = avctx->codec_tag;
-    bps = av_get_exact_bits_per_sample(avctx->codec_id);
+    int bps = av_get_exact_bits_per_sample(id);
 
     /* codecs with an exact constant bits per sample */
     if (bps > 0 && ch > 0 && frame_bytes > 0 && ch < 32768 && bps < 32768)
         return (frame_bytes * 8LL) / (bps * ch);
-    bps = avctx->bits_per_coded_sample;
+    bps = bits_per_coded_sample;
 
     /* codecs with a fixed packet duration */
     switch (id) {
@@ -3245,7 +3240,7 @@ int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
                 return (frame_bytes - 8) * 2 / ch;
             case AV_CODEC_ID_ADPCM_THP:
             case AV_CODEC_ID_ADPCM_THP_LE:
-                if (avctx->extradata)
+                if (extradata)
                     return frame_bytes * 14 / (8 * ch);
                 break;
             case AV_CODEC_ID_ADPCM_XA:
@@ -3280,7 +3275,7 @@ int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
             if (ba > 0) {
                 /* calc from frame_bytes, channels, and block_align */
                 int blocks = frame_bytes / ba;
-                switch (avctx->codec_id) {
+                switch (id) {
                 case AV_CODEC_ID_ADPCM_IMA_WAV:
                     if (bps < 2 || bps > 5)
                         return 0;
@@ -3298,7 +3293,7 @@ int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
 
             if (bps > 0) {
                 /* calc from frame_bytes, channels, and bits_per_coded_sample */
-                switch (avctx->codec_id) {
+                switch (id) {
                 case AV_CODEC_ID_PCM_DVD:
                     if(bps<4)
                         return 0;
@@ -3315,19 +3310,37 @@ int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
     }
 
     /* Fall back on using frame_size */
-    if (avctx->frame_size > 1 && frame_bytes)
-        return avctx->frame_size;
+    if (frame_size > 1 && frame_bytes)
+        return frame_size;
 
     //For WMA we currently have no other means to calculate duration thus we
     //do it here by assuming CBR, which is true for all known cases.
-    if (avctx->bit_rate>0 && frame_bytes>0 && avctx->sample_rate>0 && avctx->block_align>1) {
-        if (avctx->codec_id == AV_CODEC_ID_WMAV1 || avctx->codec_id == AV_CODEC_ID_WMAV2)
-            return  (frame_bytes * 8LL * avctx->sample_rate) / avctx->bit_rate;
+    if (bitrate > 0 && frame_bytes > 0 && sr > 0 && ba > 1) {
+        if (id == AV_CODEC_ID_WMAV1 || id == AV_CODEC_ID_WMAV2)
+            return  (frame_bytes * 8LL * sr) / bitrate;
     }
 
     return 0;
 }
 
+int av_get_audio_frame_duration(AVCodecContext *avctx, int frame_bytes)
+{
+    return get_audio_frame_duration(avctx->codec_id, avctx->sample_rate,
+                                    avctx->channels, avctx->block_align,
+                                    avctx->codec_tag, avctx->bits_per_coded_sample,
+                                    avctx->bit_rate, avctx->extradata, avctx->frame_size,
+                                    frame_bytes);
+}
+
+int av_get_audio_frame_duration2(AVCodecParameters *par, int frame_bytes)
+{
+    return get_audio_frame_duration(par->codec_id, par->sample_rate,
+                                    par->channels, par->block_align,
+                                    par->codec_tag, par->bits_per_coded_sample,
+                                    par->bit_rate, par->extradata, par->frame_size,
+                                    frame_bytes);
+}
+
 #if !HAVE_THREADS
 int ff_thread_init(AVCodecContext *s)
 {