set bps to uncompressed original sound data for compressed audio

according to aiff specs, qt set it to 16 for mace and ima4,
fail if block align is not set.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@12198 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavformat/aiff.c

@@ -189,7 +189,12 @@ static int aiff_write_header(AVFormatContext *s)
     put_be32(pb, 0);                    /* file length */
     put_tag(pb, aifc ? "AIFC" : "AIFF");
 
-    if (aifc) {
+    if (aifc) { // compressed audio
+        enc->bits_per_sample = 16;
+        if (!enc->block_align) {
+            av_log(s, AV_LOG_ERROR, "block align not set\n");
+            return -1;
+        }
         /* Version chunk */
         put_tag(pb, "FVER");
         put_be32(pb, 4);