[Mplayer-cvslog] CVS: main/libaf af.c,1.5,1.6 af.h,1.4,1.5

[Anders Johansson]

Update of /cvsroot/mplayer/main/libaf
In directory mail:/var/tmp.root/cvs-serv10145

Modified Files:
	af.c af.h 
Log Message:
Adding function for estimating required buffer length

Index: af.c
===================================================================
RCS file: /cvsroot/mplayer/main/libaf/af.c,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -r1.5 -r1.6
--- af.c	3 Oct 2002 12:43:39 -0000	1.5
+++ af.c	5 Oct 2002 11:02:39 -0000	1.6
@@ -408,6 +408,54 @@
   return t * (((len/t) * mul.d - 1)/mul.n);
 }
 
+/* Calculate how long the input IN to the filters should be to produce
+   a certain output length OUT but with the following three constraints:
+   1. IN <= max_insize, where max_insize is the maximum possible input
+      block length
+   2. OUT <= max_outsize, where max_outsize is the maximum possible
+      output block length
+   3. If possible OUT >= len. 
+   Return -1 in case of error */ 
+int af_calc_insize_constrained(af_stream_t* s, int len,
+			       int max_outsize,int max_insize)
+{
+  int t   = s->input.bps*s->input.nch;
+  int in  = 0;
+  int out = 0;
+  af_instance_t* af=s->first; 
+  register frac_t mul = {1,1};
+  // Iterate through all filters and calculate total multiplication factor
+  do{
+    mul.n *= af->mul.n;
+    mul.d *= af->mul.d;
+    af=af->next;
+  }while(af);
+  in = t * (((len/t) * mul.d)/mul.n);
+
+  // Try to meet constraint nr 3. 
+  out = t * (((in/t)*mul.n + 1)/mul.d);
+  while(in <= max_insize && out <= max_outsize){
+    printf("debug in = %i out = %i  \n",in,out);
+
+    if(out > len)
+      return in;
+    out = t * (((in/t)*mul.n + 1)/mul.d);
+    in+=t;
+  }
+  
+  // Could no meet constraint nr 3.
+  while((out > max_outsize || in > max_insize) && in > 1)
+  {
+    in-=t;
+    out = t * (((in/t)*mul.n + 1)/mul.d);
+  }
+  if(in > 1)
+    return in;
+
+  // Input parameters are probably incorrect
+  return -1;
+}
+
 /* Helper function called by the macro with the same name this
    function should not be called directly */
 inline int af_resize_local_buffer(af_instance_t* af, af_data_t* data)

Index: af.h
===================================================================
RCS file: /cvsroot/mplayer/main/libaf/af.h,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- af.h	3 Oct 2002 12:44:58 -0000	1.4
+++ af.h	5 Oct 2002 11:02:39 -0000	1.5
@@ -146,7 +146,16 @@
    the input length required to produce the output length "len". The
    calculated length is <= the actual length */
 int af_inputlen(af_stream_t* s, int len);
-
+/* Calculate how long the input IN to the filters should be to produce
+   a certain output length OUT but with the following three constraints:
+   1. IN <= max_insize, where max_insize is the maximum possible input
+      block length
+   2. OUT <= max_outsize, where max_outsize is the maximum possible
+      output block length
+   3. If possible OUT >= len. 
+   Return -1 in case of error */ 
+int af_calc_insize_constrained(af_stream_t* s, int len,
+			       int max_outsize,int max_insize);
 
 
 // Helper functions and macros used inside the audio filters