2 byte shorter userdata for mpeg4

in the past it was startcode,string,00,7F,startcode
now it is startcode,string,stratcode
both are mpeg4 compliant, as according to the standard the userdata lasts until the next 00 00 01 (startcode prefix) but some very primitive decoders which simply skip until the first 00 byte and then expect the next valid startcode might fail with the old variant, just a theory though (didnt test if quicktime can decode it now)

Originally committed as revision 2767 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/common.c

@@ -104,13 +104,14 @@ void flush_put_bits(PutBitContext *s)
 
 #ifdef CONFIG_ENCODERS
 
-void put_string(PutBitContext * pbc, char *s)
+void put_string(PutBitContext * pbc, char *s, int put_zero)
 {
     while(*s){
         put_bits(pbc, 8, *s);
         s++;
     }
-    put_bits(pbc, 8, 0);
+    if(put_zero)
+        put_bits(pbc, 8, 0);
 }
 
 /* bit input functions */

libavcodec/common.h

@@ -291,7 +291,7 @@ void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size);
 int put_bits_count(PutBitContext *s);
 void align_put_bits(PutBitContext *s);
 void flush_put_bits(PutBitContext *s);
-void put_string(PutBitContext * pbc, char *s);
+void put_string(PutBitContext * pbc, char *s, int put_zero);
 
 /* bit input */
 
@@ -1142,7 +1142,7 @@ uint64_t tstart= rdtsc();\
 
 #define STOP_TIMER(id) \
 tend= rdtsc();\
-if(tcount<2 || tend - tstart < 4*tsum/tcount){\
+if(tcount<2 || tend - tstart < 8*tsum/tcount){\
     tsum+= tend - tstart;\
     tcount++;\
 }else\

libavcodec/h263.c

@@ -2326,8 +2326,7 @@ static void mpeg4_encode_vol_header(MpegEncContext * s, int vo_number, int vol_n
     if(!(s->flags & CODEC_FLAG_BITEXACT)){
         put_bits(&s->pb, 16, 0);
         put_bits(&s->pb, 16, 0x1B2);	/* user_data */
-	put_string(&s->pb, LIBAVCODEC_IDENT);
-        ff_mpeg4_stuffing(&s->pb);
+	put_string(&s->pb, LIBAVCODEC_IDENT, 0);
     }
 }
 

libavcodec/mjpeg.c

@@ -378,7 +378,7 @@ static void jpeg_put_comments(MpegEncContext *s)
     /* JFIF header */
     put_marker(p, APP0);
     put_bits(p, 16, 16);
-    put_string(p, "JFIF"); /* this puts the trailing zero-byte too */
+    put_string(p, "JFIF", 1); /* this puts the trailing zero-byte too */
     put_bits(p, 16, 0x0201); /* v 1.02 */
     put_bits(p, 8, 0); /* units type: 0 - aspect ratio */
     put_bits(p, 16, s->avctx->sample_aspect_ratio.num);
@@ -393,7 +393,7 @@ static void jpeg_put_comments(MpegEncContext *s)
         flush_put_bits(p);
         ptr = pbBufPtr(p);
         put_bits(p, 16, 0); /* patched later */
-        put_string(p, LIBAVCODEC_IDENT);
+        put_string(p, LIBAVCODEC_IDENT, 1);
         size = strlen(LIBAVCODEC_IDENT)+3;
         ptr[0] = size >> 8;
         ptr[1] = size;