diff --git a/ffmpeg.c b/ffmpeg.c
index a160e8abd7..a700b266f9 100644
--- a/ffmpeg.c
+++ b/ffmpeg.c
@@ -2078,7 +2078,7 @@ static void opt_input_file(const char *filename)
         case CODEC_TYPE_VIDEO:
             frame_height = enc->height;
             frame_width = enc->width;
-	    frame_aspect_ratio = enc->aspect_ratio;
+	    frame_aspect_ratio = av_q2d(enc->sample_aspect_ratio) * enc->width / enc->height;
 	    frame_pix_fmt = enc->pix_fmt;
             rfps      = ic->streams[i]->r_frame_rate;
             rfps_base = ic->streams[i]->r_frame_rate_base;
@@ -2239,7 +2239,7 @@ static void opt_output_file(const char *filename)
                 
                 video_enc->width = frame_width;
                 video_enc->height = frame_height;
-		video_enc->aspect_ratio = frame_aspect_ratio;
+		video_enc->sample_aspect_ratio = av_d2q(frame_aspect_ratio*frame_height/frame_width, 30000);
 		video_enc->pix_fmt = frame_pix_fmt;
 
                 if (!intra_only)
diff --git a/ffplay.c b/ffplay.c
index 13a96e4112..5105ad1d48 100644
--- a/ffplay.c
+++ b/ffplay.c
@@ -330,7 +330,8 @@ static void video_image_display(VideoState *is)
     vp = &is->pictq[is->pictq_rindex];
     if (vp->bmp) {
         /* XXX: use variable in the frame */
-        aspect_ratio = is->video_st->codec.aspect_ratio;
+        aspect_ratio = av_q2d(is->video_st->codec.sample_aspect_ratio) 
+            * is->video_st->codec.width / is->video_st->codec.height;;
         if (aspect_ratio <= 0.0)
             aspect_ratio = (float)is->video_st->codec.width / 
                 (float)is->video_st->codec.height;
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 4ae6c3a663..00e7c09402 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -18,7 +18,7 @@ OBJS= common.o utils.o mem.o allcodecs.o \
       fft.o mdct.o mace.o huffyuv.o cyuv.o opts.o raw.o h264.o golomb.o \
       vp3.o asv1.o 4xm.o cabac.o ffv1.o ra144.o ra288.o vcr1.o cljr.o \
       roqvideo.o dpcm.o interplayvideo.o xan.o rpza.o cinepak.o msrle.o \
-      msvideo1.o vqavideo.o idcinvideo.o adx.o
+      msvideo1.o vqavideo.o idcinvideo.o adx.o rational.o
 
 ifeq ($(AMR_NB),yes)
 ifeq ($(AMR_NB_FIXED),yes)
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index f6c052a04b..47ab4c0950 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -12,10 +12,11 @@ extern "C" {
 #endif
 
 #include "common.h"
+#include "rational.h"
 
 #define FFMPEG_VERSION_INT     0x000408
 #define FFMPEG_VERSION         "0.4.8"
-#define LIBAVCODEC_BUILD       4686
+#define LIBAVCODEC_BUILD       4687
 
 #define LIBAVCODEC_VERSION_INT FFMPEG_VERSION_INT
 #define LIBAVCODEC_VERSION     FFMPEG_VERSION
@@ -1034,11 +1035,11 @@ typedef struct AVCodecContext {
 #define FF_PRED_MEDIAN 2
     
     /**
-     * aspect ratio (0 if unknown).
+     * sample aspect ratio (0 if unknown).
      * - encoding: set by user.
      * - decoding: set by lavc.
      */
-    float aspect_ratio;
+    AVRational sample_aspect_ratio;
 
     /**
      * the picture in the bitstream.
diff --git a/libavcodec/common.c b/libavcodec/common.c
index 58d625f099..f37c2c9eba 100644
--- a/libavcodec/common.c
+++ b/libavcodec/common.c
@@ -386,29 +386,3 @@ int64_t ff_gcd(int64_t a, int64_t b){
     if(b) return ff_gcd(b, a%b);
     else  return a;
 }
-
-void ff_float2fraction(int *nom_arg, int *denom_arg, double f, int max){
-    double best_diff=1E10, diff;
-    int best_denom=1, best_nom=1;
-    int nom, denom, gcd;
-    
-    //brute force here, perhaps we should try continued fractions if we need large max ...
-    for(denom=1; denom<=max; denom++){
-        nom= (int)(f*denom + 0.5);
-        if(nom<=0 || nom>max) continue;
-        
-        diff= ABS( f - (double)nom / (double)denom );
-        if(diff < best_diff){
-            best_diff= diff;
-            best_nom= nom;
-            best_denom= denom;
-        }
-    }
-    
-    gcd= ff_gcd(best_nom, best_denom);
-    best_nom   /= gcd;
-    best_denom /= gcd;
-
-    *nom_arg= best_nom;
-    *denom_arg= best_denom;
-}
diff --git a/libavcodec/common.h b/libavcodec/common.h
index 7149ef8085..9740acb586 100644
--- a/libavcodec/common.h
+++ b/libavcodec/common.h
@@ -1056,9 +1056,6 @@ static inline int ff_get_fourcc(const char *s){
 #define MKBETAG(a,b,c,d) (d | (c << 8) | (b << 16) | (a << 24))
 
 
-void ff_float2fraction(int *nom_arg, int *denom_arg, double f, int max);
-
-
 #ifdef ARCH_X86
 #define MASK_ABS(mask, level)\
             asm volatile(\
diff --git a/libavcodec/h263.c b/libavcodec/h263.c
index 5d03ba611e..0b09dc7311 100644
--- a/libavcodec/h263.c
+++ b/libavcodec/h263.c
@@ -131,19 +131,13 @@ int h263_get_picture_format(int width, int height)
 
 #ifdef CONFIG_ENCODERS
 
-static void float_aspect_to_info(MpegEncContext * s, float aspect){
+static void aspect_to_info(MpegEncContext * s, AVRational aspect){
     int i;
 
-    aspect*= s->height/(double)s->width;
-//printf("%f\n", aspect);
-    
-    if(aspect==0) aspect= 1.0;
+    if(aspect.num==0) aspect= (AVRational){1,1};
 
-    ff_float2fraction(&s->aspected_width, &s->aspected_height, aspect, 255);
-
-//printf("%d %d\n", s->aspected_width, s->aspected_height);
     for(i=1; i<6; i++){
-        if(s->aspected_width == pixel_aspect[i][0] && s->aspected_height== pixel_aspect[i][1]){
+        if(av_cmp_q(pixel_aspect[i], aspect) == 0){
             s->aspect_ratio_info=i;
             return;
         }
@@ -270,16 +264,15 @@ void h263_encode_picture_header(MpegEncContext * s, int picture_number)
 		
 		if (format == 7) {
             /* Custom Picture Format (CPFMT) */
-            float_aspect_to_info(s, s->avctx->aspect_ratio);
+            aspect_to_info(s, s->avctx->sample_aspect_ratio);
 
             put_bits(&s->pb,4,s->aspect_ratio_info);
             put_bits(&s->pb,9,(s->width >> 2) - 1);
             put_bits(&s->pb,1,1); /* "1" to prevent start code emulation */
             put_bits(&s->pb,9,(s->height >> 2));
-	    if (s->aspect_ratio_info == FF_ASPECT_EXTENDED)
-	    {
-		put_bits(&s->pb, 8, s->aspected_width);
-		put_bits(&s->pb, 8, s->aspected_height);
+            if (s->aspect_ratio_info == FF_ASPECT_EXTENDED){
+                put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.num);
+                put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.den);
 	    }
         }
         
@@ -1949,13 +1942,12 @@ static void mpeg4_encode_vol_header(MpegEncContext * s, int vo_number, int vol_n
       put_bits(&s->pb, 4, vo_ver_id);	/* is obj layer ver id */
       put_bits(&s->pb, 3, 1);		/* is obj layer priority */
     
-    float_aspect_to_info(s, s->avctx->aspect_ratio);
+    aspect_to_info(s, s->avctx->sample_aspect_ratio);
 
     put_bits(&s->pb, 4, s->aspect_ratio_info);/* aspect ratio info */
-    if (s->aspect_ratio_info == FF_ASPECT_EXTENDED)
-    {
-	put_bits(&s->pb, 8, s->aspected_width);
-	put_bits(&s->pb, 8, s->aspected_height);
+    if (s->aspect_ratio_info == FF_ASPECT_EXTENDED){
+        put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.num);
+        put_bits(&s->pb, 8, s->avctx->sample_aspect_ratio.den);
     }
 
     if(s->low_delay){
@@ -4341,11 +4333,10 @@ int h263_decode_picture_header(MpegEncContext *s)
                 dprintf("\nH.263+ Custom picture: %dx%d\n",width,height);
                 if (s->aspect_ratio_info == FF_ASPECT_EXTENDED) {
                     /* aspected dimensions */
-		    s->aspected_width = get_bits(&s->gb, 8);
-		    s->aspected_height = get_bits(&s->gb, 8);
+                    s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 8);
+                    s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 8);
                 }else{
-                    s->aspected_width = pixel_aspect[s->aspect_ratio_info][0];
-                    s->aspected_height= pixel_aspect[s->aspect_ratio_info][1];
+                    s->avctx->sample_aspect_ratio= pixel_aspect[s->aspect_ratio_info];
                 }
             } else {
                 width = h263_format[format][0];
@@ -4632,11 +4623,10 @@ static int decode_vol_header(MpegEncContext *s, GetBitContext *gb){
 //printf("vo type:%d\n",s->vo_type);
     s->aspect_ratio_info= get_bits(gb, 4);
     if(s->aspect_ratio_info == FF_ASPECT_EXTENDED){	    
-        s->aspected_width = get_bits(gb, 8); // par_width
-        s->aspected_height = get_bits(gb, 8); // par_height
+        s->avctx->sample_aspect_ratio.num= get_bits(gb, 8); // par_width
+        s->avctx->sample_aspect_ratio.den= get_bits(gb, 8); // par_height
     }else{
-        s->aspected_width = pixel_aspect[s->aspect_ratio_info][0];
-        s->aspected_height= pixel_aspect[s->aspect_ratio_info][1];
+        s->avctx->sample_aspect_ratio= pixel_aspect[s->aspect_ratio_info];
     }
 
     if ((s->vol_control_parameters=get_bits1(gb))) { /* vol control parameter */
diff --git a/libavcodec/h263dec.c b/libavcodec/h263dec.c
index f4f0c29490..f83ff54420 100644
--- a/libavcodec/h263dec.c
+++ b/libavcodec/h263dec.c
@@ -393,7 +393,6 @@ int ff_h263_decode_frame(AVCodecContext *avctx,
     MpegEncContext *s = avctx->priv_data;
     int ret;
     AVFrame *pict = data; 
-    float new_aspect;
     
 #ifdef PRINT_FRAME_TIME
 uint64_t time= rdtsc();
@@ -602,13 +601,8 @@ retry:
         /* and other parameters. So then we could init the picture   */
         /* FIXME: By the way H263 decoder is evolving it should have */
         /* an H263EncContext                                         */
-    if(s->aspected_height)
-        new_aspect= s->aspected_width*s->width / (float)(s->height*s->aspected_height);
-    else
-        new_aspect=0;
     
-    if (   s->width != avctx->width || s->height != avctx->height 
-        || ABS(new_aspect - avctx->aspect_ratio) > 0.001) {
+    if (   s->width != avctx->width || s->height != avctx->height) {
         /* H.263 could change picture size any time */
         ParseContext pc= s->parse_context; //FIXME move these demuxng hack to avformat
         s->parse_context.buffer=0;
@@ -618,7 +612,6 @@ retry:
     if (!s->context_initialized) {
         avctx->width = s->width;
         avctx->height = s->height;
-        avctx->aspect_ratio= new_aspect;
 
         goto retry;
     }
diff --git a/libavcodec/h264.c b/libavcodec/h264.c
index f186fc26b2..97589ce827 100644
--- a/libavcodec/h264.c
+++ b/libavcodec/h264.c
@@ -79,8 +79,7 @@ typedef struct SPS{
     int crop_top;               ///< frame_cropping_rect_top_offset
     int crop_bottom;            ///< frame_cropping_rect_bottom_offset
     int vui_parameters_present_flag;
-    int sar_width;
-    int sar_height;
+    AVRational sar;
     short offset_for_ref_frame[256]; //FIXME dyn aloc?
 }SPS;
 
@@ -2829,7 +2828,6 @@ static int decode_slice_header(H264Context *h){
     int first_mb_in_slice, pps_id;
     int num_ref_idx_active_override_flag;
     static const uint8_t slice_type_map[5]= {P_TYPE, B_TYPE, I_TYPE, SP_TYPE, SI_TYPE};
-    float new_aspect;
 
     s->current_picture.reference= h->nal_ref_idc != 0;
 
@@ -2881,14 +2879,8 @@ static int decode_slice_header(H264Context *h){
     else
         s->height= 16*s->mb_height - 4*(h->sps.crop_top  + h->sps.crop_bottom); //FIXME recheck
     
-    if(s->aspected_height) //FIXME emms at end of slice ?
-        new_aspect= h->sps.sar_width*s->width / (float)(s->height*h->sps.sar_height);
-    else
-        new_aspect=0;
-
     if (s->context_initialized 
-        && (   s->width != s->avctx->width || s->height != s->avctx->height 
-            || ABS(new_aspect - s->avctx->aspect_ratio) > 0.001)) {
+        && (   s->width != s->avctx->width || s->height != s->avctx->height)) {
         free_tables(h);
         MPV_common_end(s);
     }
@@ -2900,7 +2892,7 @@ static int decode_slice_header(H264Context *h){
 
         s->avctx->width = s->width;
         s->avctx->height = s->height;
-        s->avctx->aspect_ratio= new_aspect;
+        s->avctx->sample_aspect_ratio= h->sps.sar;
     }
 
     if(first_mb_in_slice == 0){
@@ -3736,18 +3728,17 @@ static inline int decode_vui_parameters(H264Context *h, SPS *sps){
     if( aspect_ratio_info_present_flag ) {
         aspect_ratio_idc= get_bits(&s->gb, 8);
         if( aspect_ratio_idc == EXTENDED_SAR ) {
-            sps->sar_width= get_bits(&s->gb, 16);
-            sps->sar_height= get_bits(&s->gb, 16);
+            sps->sar.num= get_bits(&s->gb, 16);
+            sps->sar.den= get_bits(&s->gb, 16);
         }else if(aspect_ratio_idc < 16){
-            sps->sar_width=  pixel_aspect[aspect_ratio_idc][0];
-            sps->sar_height= pixel_aspect[aspect_ratio_idc][1];
+            sps->sar=  pixel_aspect[aspect_ratio_idc];
         }else{
             fprintf(stderr, "illegal aspect ratio\n");
             return -1;
         }
     }else{
-        sps->sar_width= 
-        sps->sar_height= 0;
+        sps->sar.num= 
+        sps->sar.den= 0;
     }
 //            s->avctx->aspect_ratio= sar_width*s->width / (float)(s->height*sar_height);
 #if 0
diff --git a/libavcodec/h264data.h b/libavcodec/h264data.h
index 0a7ad50148..40a2522532 100644
--- a/libavcodec/h264data.h
+++ b/libavcodec/h264data.h
@@ -51,8 +51,8 @@
 
 #define EXTENDED_SAR          255
 
-static const uint16_t pixel_aspect[16][2]={
- {0, 0},
+static const AVRational pixel_aspect[14]={
+ {0, 1},
  {1, 1},
  {12, 11},
  {10, 11},
diff --git a/libavcodec/mjpeg.c b/libavcodec/mjpeg.c
index f67f280a88..f2267faf8f 100644
--- a/libavcodec/mjpeg.c
+++ b/libavcodec/mjpeg.c
@@ -381,28 +381,8 @@ static void jpeg_put_comments(MpegEncContext *s)
     put_string(p, "JFIF"); /* 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 */
-    switch(s->aspect_ratio_info)
-    {
-	case FF_ASPECT_4_3_625:
-	case FF_ASPECT_4_3_525:
-	    put_bits(p, 16, 4); 
-	    put_bits(p, 16, 3);
-	    break;
-	case FF_ASPECT_16_9_625:
-	case FF_ASPECT_16_9_525:
-	    put_bits(p, 16, 16); 
-	    put_bits(p, 16, 9);
-	    break;
-	case FF_ASPECT_EXTENDED:
-	    put_bits(p, 16, s->aspected_width);
-	    put_bits(p, 16, s->aspected_height);
-	    break;
-	case FF_ASPECT_SQUARE:
-	default:
-	    put_bits(p, 16, 1); /* aspect: 1:1 */
-	    put_bits(p, 16, 1);
-	    break;
-    }
+    put_bits(p, 16, s->avctx->sample_aspect_ratio.num);
+    put_bits(p, 16, s->avctx->sample_aspect_ratio.den);
     put_bits(p, 8, 0); /* thumbnail width */
     put_bits(p, 8, 0); /* thumbnail height */
     }
@@ -1547,29 +1527,10 @@ static int mjpeg_decode_app(MJpegDecodeContext *s)
 	skip_bits(&s->gb, 8); /* the trailing zero-byte */
 	printf("mjpeg: JFIF header found (version: %x.%x)\n",
 	    get_bits(&s->gb, 8), get_bits(&s->gb, 8));
-	if (get_bits(&s->gb, 8) == 0)
-	{
-	    int x_density, y_density; 
-	    x_density = get_bits(&s->gb, 16);
-	    y_density = get_bits(&s->gb, 16);
+        skip_bits(&s->gb, 8);
 
-	    dprintf("x/y density: %d (%f), %d (%f)\n", x_density,
-		(float)x_density, y_density, (float)y_density);
-#if 0
-            //MN: needs to be checked
-            if(x_density)
-//                s->avctx->aspect_ratio= s->width*y_density/((float)s->height*x_density);
-		s->avctx->aspect_ratio = (float)x_density/y_density;
-		/* it's better, but every JFIF I have seen stores 1:1 */
-            else
-                s->avctx->aspect_ratio= 0.0;
-#endif
-	}
-	else
-	{
-	    skip_bits(&s->gb, 16);
-	    skip_bits(&s->gb, 16);
-	}
+        s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 16);
+        s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 16);
 
 	t_w = get_bits(&s->gb, 8);
 	t_h = get_bits(&s->gb, 8);
@@ -2085,7 +2046,7 @@ static int sp5x_decode_frame(AVCodecContext *avctx,
     memcpy(recoded+j, &sp5x_data_sos[0], sizeof(sp5x_data_sos));
     j += sizeof(sp5x_data_sos);
 
-    for (i = 14; i < buf_size, j < buf_size+1024-2; i++)
+    for (i = 14; i < buf_size && j < buf_size+1024-2; i++)
     {
 	recoded[j++] = buf[i];
 	if (buf[i] == 0xff)
diff --git a/libavcodec/mpeg12.c b/libavcodec/mpeg12.c
index 015033bf36..f054e00d0d 100644
--- a/libavcodec/mpeg12.c
+++ b/libavcodec/mpeg12.c
@@ -190,10 +190,10 @@ static void mpeg1_encode_sequence_header(MpegEncContext *s)
         int n, i;
         uint64_t time_code;
         float best_aspect_error= 1E10;
-        float aspect_ratio= s->avctx->aspect_ratio;
+        float aspect_ratio= av_q2d(s->avctx->sample_aspect_ratio);
         int constraint_parameter_flag;
         
-        if(aspect_ratio==0.0) aspect_ratio= s->width / (float)s->height; //pixel aspect 1:1 (VGA)
+        if(aspect_ratio==0.0) aspect_ratio= 1.0; //pixel aspect 1:1 (VGA)
         
         if (s->current_picture.key_frame) {
             /* mpeg1 header repeated every gop */
@@ -219,7 +219,7 @@ static void mpeg1_encode_sequence_header(MpegEncContext *s)
             put_bits(&s->pb, 12, s->height);
             
             for(i=1; i<15; i++){
-                float error= mpeg1_aspect[i] - s->width/(s->height*aspect_ratio);
+                float error= mpeg1_aspect[i] - aspect_ratio;
                 error= ABS(error);
                 
                 if(error < best_aspect_error){
@@ -1742,7 +1742,6 @@ static void mpeg_decode_sequence_extension(MpegEncContext *s)
     int bit_rate_ext, vbv_buf_ext;
     int frame_rate_ext_n, frame_rate_ext_d;
     int level, profile;
-    float aspect;
 
     skip_bits(&s->gb, 1); /* profil and level esc*/
     profile= get_bits(&s->gb, 3);
@@ -1774,9 +1773,15 @@ static void mpeg_decode_sequence_extension(MpegEncContext *s)
     s->codec_id= s->avctx->codec_id= CODEC_ID_MPEG2VIDEO;
     s->avctx->sub_id = 2; /* indicates mpeg2 found */
 
-    aspect= mpeg2_aspect[s->aspect_ratio_info];
-    if(aspect>0.0)      s->avctx->aspect_ratio= s->width/(aspect*s->height);
-    else if(aspect<0.0) s->avctx->aspect_ratio= -1.0/aspect;
+    if(s->aspect_ratio_info <= 1)
+        s->avctx->sample_aspect_ratio= mpeg2_aspect[s->aspect_ratio_info];
+    else{
+        s->avctx->sample_aspect_ratio= 
+            av_div_q(
+                mpeg2_aspect[s->aspect_ratio_info], 
+                (AVRational){s->width, s->height}
+            );
+    }
     
     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
         printf("profile: %d, level: %d \n", profile, level);
@@ -1802,8 +1807,12 @@ static void mpeg_decode_sequence_display_extension(Mpeg1Context *s1)
     s1->pan_scan.width= 16*w;
     s1->pan_scan.height=16*h;
 
-    if(mpeg2_aspect[s->aspect_ratio_info] < 0.0)
-        s->avctx->aspect_ratio*= (s->width * h)/(float)(s->height * w);
+    if(s->aspect_ratio_info > 1)
+        s->avctx->sample_aspect_ratio= 
+            av_div_q(
+                mpeg2_aspect[s->aspect_ratio_info], 
+                (AVRational){w, h}
+            );
     
     if(s->avctx->debug & FF_DEBUG_PICT_INFO)
         printf("sde w:%d, h:%d\n", w, h);
@@ -2243,7 +2252,7 @@ static int mpeg1_decode_sequence(AVCodecContext *avctx,
     s->aspect_ratio_info= get_bits(&s->gb, 4);
     if(s->codec_id == CODEC_ID_MPEG1VIDEO){
         aspect= mpeg1_aspect[s->aspect_ratio_info];
-        if(aspect!=0.0) avctx->aspect_ratio= width/(aspect*height);
+        if(aspect!=0.0) avctx->sample_aspect_ratio= av_d2q(aspect, 30000);
     }
 
     s->frame_rate_index = get_bits(&s->gb, 4);
diff --git a/libavcodec/mpeg12data.h b/libavcodec/mpeg12data.h
index 938897528c..dd94bb572b 100644
--- a/libavcodec/mpeg12data.h
+++ b/libavcodec/mpeg12data.h
@@ -416,11 +416,22 @@ static const float mpeg1_aspect[16]={
     1.2015,
 };
 
-static const float mpeg2_aspect[16]={
-    0,
-    1.0,
-    -3.0/4.0,
-    -9.0/16.0,
-    -1.0/2.21,
+static const AVRational mpeg2_aspect[16]={
+    {0,1},
+    {1,1},
+    {4,3},
+    {16,9},
+    {221,100},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
+    {0,1},
 };
 
diff --git a/libavcodec/mpeg4data.h b/libavcodec/mpeg4data.h
index d48e874687..0092a9f5e0 100644
--- a/libavcodec/mpeg4data.h
+++ b/libavcodec/mpeg4data.h
@@ -341,23 +341,23 @@ static const uint8_t mb_type_b_tab[4][2] = {
  {1, 1}, {1, 2}, {1, 3}, {1, 4},
 };
 
-static const uint16_t pixel_aspect[16][2]={
- {0, 0},
+static const AVRational pixel_aspect[16]={
+ {0, 1},
  {1, 1},
  {12, 11},
  {10, 11},
  {16, 11},
  {40, 33},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
- {0, 0},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
+ {0, 1},
 };
 
 /* these matrixes will be permuted for the idct */
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index 74fa23d3b2..30432c1731 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -554,8 +554,6 @@ typedef struct MpegEncContext {
     int new_pred;
     int reduced_res_vop;
     int aspect_ratio_info; //FIXME remove
-    int aspected_width;    //FIXME remove
-    int aspected_height;   //FIXME remove
     int sprite_warping_accuracy;
     int low_latency_sprite;
     int data_partitioning;           ///< data partitioning flag from header 
diff --git a/libavcodec/rational.c b/libavcodec/rational.c
new file mode 100644
index 0000000000..f2a579abca
--- /dev/null
+++ b/libavcodec/rational.c
@@ -0,0 +1,61 @@
+/*
+ * Rational numbers
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+ 
+/**
+ * @file rational.c
+ * Rational numbers
+ * @author Michael Niedermayer <michaelni@gmx.at>
+ */
+
+//#include <math.h>
+#include <limits.h>
+ 
+#include "common.h"
+#include "avcodec.h"
+#include "rational.h"
+
+AVRational av_mul_q(AVRational b, AVRational c){
+    av_reduce(&b.num, &b.den, b.num * (int64_t)c.num, b.den * (int64_t)c.den, INT_MAX);
+    return b;
+}
+
+AVRational av_div_q(AVRational b, AVRational c){
+    av_reduce(&b.num, &b.den, b.num * (int64_t)c.den, b.den * (int64_t)c.num, INT_MAX);
+    return b;
+}
+
+AVRational av_add_q(AVRational b, AVRational c){
+    av_reduce(&b.num, &b.den, b.num * (int64_t)c.den + c.num * (int64_t)b.den, b.den * (int64_t)c.den, INT_MAX);
+    return b;
+}
+
+AVRational av_sub_q(AVRational b, AVRational c){
+    av_reduce(&b.num, &b.den, b.num * (int64_t)c.den - c.num * (int64_t)b.den, b.den * (int64_t)c.den, INT_MAX);
+    return b;
+}
+
+AVRational av_d2q(double d, int max){
+    AVRational a;
+    int exponent= FFMAX( (int)log2(ABS(d) + 1e-20), 0);
+    int64_t den= 1LL << (61 - exponent);
+    av_reduce(&a.num, &a.den, (int64_t)(d * den + 0.5), den, max);
+
+    return a;
+}
diff --git a/libavcodec/rational.h b/libavcodec/rational.h
new file mode 100644
index 0000000000..d5fc77f1a6
--- /dev/null
+++ b/libavcodec/rational.h
@@ -0,0 +1,53 @@
+/*
+ * Rational numbers
+ * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ */
+ 
+/**
+ * @file rational.h
+ * Rational numbers.
+ * @author Michael Niedermayer <michaelni@gmx.at>
+ */
+
+#ifndef RATIONAL_H
+#define RATIONAL_H
+
+typedef struct AVRational{
+    int num; 
+    int den;
+} AVRational;
+
+static inline int av_cmp_q(AVRational a, AVRational b){
+    const int64_t tmp= a.num * (int64_t)b.den - b.num * (int64_t)a.den;
+
+    if     (tmp <  0) return -1;
+    else if(tmp == 0) return  0;
+    else              return  1;
+}
+
+static inline double av_q2d(AVRational a){
+    return a.num / (double) a.den;
+}
+
+AVRational av_mul_q(AVRational b, AVRational c);
+AVRational av_div_q(AVRational b, AVRational c);
+AVRational av_add_q(AVRational b, AVRational c);
+AVRational av_sub_q(AVRational b, AVRational c);
+AVRational av_d2q(double d, int max);
+
+#endif // RATIONAL_H
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index ac4a12fb16..f9ed4f5ab6 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -314,6 +314,7 @@ void avcodec_get_context_defaults(AVCodecContext *s){
     s->me_subpel_quality=8;
     s->lmin= FF_QP2LAMBDA * s->qmin;
     s->lmax= FF_QP2LAMBDA * s->qmax;
+    s->sample_aspect_ratio= (AVRational){0,1};
     
     s->intra_quant_bias= FF_DEFAULT_QUANT_BIAS;
     s->inter_quant_bias= FF_DEFAULT_QUANT_BIAS;
diff --git a/libavformat/dv.c b/libavformat/dv.c
index 62992fa8fc..56e3160162 100644
--- a/libavformat/dv.c
+++ b/libavformat/dv.c
@@ -556,10 +556,12 @@ static int dv_extract_video_info(uint8_t* frame, AVCodecContext* avctx)
         avctx->height = sys->height;
         avctx->pix_fmt = sys->pix_fmt;
         vsc_pack = dv_extract_pack(frame, dv_video_control);
+        /* MN: someone please fill in the correct SAR for dv, i dont have the standard doc so i cant, allthough its very likely the same as MPEG4 (12:11 10:11 16:11 40:33) */
         if (vsc_pack && (vsc_pack[2] & 0x07) == (apt?0x02:0x07))
-            avctx->aspect_ratio = 16.0 / 9.0;
+            avctx->sample_aspect_ratio = (AVRational){16,9};
         else
-            avctx->aspect_ratio = 4.0 / 3.0;
+            avctx->sample_aspect_ratio = (AVRational){4,3};
+        avctx->sample_aspect_ratio = av_div_q(avctx->sample_aspect_ratio, (AVRational){sys->width,sys->height});
 	size = sys->frame_size;
     }
     return size;
@@ -660,7 +662,7 @@ DVMuxContext* dv_init_mux(AVFormatContext* s)
     c->has_audio = c->has_video = 0;
     c->start_time = time(NULL);
     c->aspect = 0; /* 4:3 is the default */
-    if ((int)(vst->codec.aspect_ratio * 10) == 17) /* 16:9 */ 
+    if ((int)(av_q2d(vst->codec.sample_aspect_ratio) * vst->codec.width / vst->codec.height * 10) == 17) /* 16:9 */ 
         c->aspect = 0x07;
 
     if (fifo_init(&c->audio_data, 100*AVCODEC_MAX_AUDIO_FRAME_SIZE) < 0)
diff --git a/libavformat/yuv4mpeg.c b/libavformat/yuv4mpeg.c
index e9f08c8343..25eef070fe 100644
--- a/libavformat/yuv4mpeg.c
+++ b/libavformat/yuv4mpeg.c
@@ -24,18 +24,11 @@
 
 #ifdef CONFIG_ENCODERS
 
-
-static struct { int n; int d;} SAR[] = {{10, 11}, /*  4:3 NTSC */
-	                                {59, 54}, /*  4:3 PAL  */
-	                                {40, 33}, /* 16:9 NTSC */
-				       {118, 81}, /* 16:9 PAL  */
-					{ 1,  1}};/* should always be the last */
-
 static int yuv4_generate_header(AVFormatContext *s, char* buf)
 {
     AVStream *st;
     int width, height;
-    int raten, rated, aspectn, aspectd, n, i;
+    int raten, rated, aspectn, aspectd, n;
     char inter;
 
     st = s->streams[0];
@@ -44,13 +37,8 @@ static int yuv4_generate_header(AVFormatContext *s, char* buf)
 
     av_reduce(&raten, &rated, st->codec.frame_rate, st->codec.frame_rate_base, (1UL<<31)-1);
     
-    for (i=0; i<sizeof(SAR)/sizeof(SAR[0])-1; i++) {
-       if (ABS(st->codec.aspect_ratio -
-	       (float)SAR[i].n/SAR[i].d * (float)width/height) < 0.05)
-		  break;
-    }
-    aspectn = SAR[i].n;
-    aspectd = SAR[i].d;
+    aspectn = st->codec.sample_aspect_ratio.num;
+    aspectd = st->codec.sample_aspect_ratio.den;
     
     inter = 'p'; /* progressive is the default */
     if (st->codec.coded_frame && st->codec.coded_frame->interlaced_frame) {
@@ -200,6 +188,7 @@ static int yuv4_read_header(AVFormatContext *s, AVFormatParameters *ap)
     st->codec.pix_fmt = PIX_FMT_YUV420P;
     st->codec.codec_type = CODEC_TYPE_VIDEO;
     st->codec.codec_id = CODEC_ID_RAWVIDEO;
+    st->codec.sample_aspect_ratio= (AVRational){aspectn, aspectd};
 
     return 0;
 }