Ticket #1655: aligndim.diff

libavcodec/utils.c

@@ -117 +117 @@
 
 #define INTERNAL_BUFFER_SIZE 32
 
-void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height){
+void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height, int *linesize_align){
     int w_align= 1;
     int h_align= 1;
 
@@ -180 +180 @@
     *height= FFALIGN(*height, h_align);
     if(s->codec_id == CODEC_ID_H264)
         *height+=2; // some of the optimized chroma MC reads one line too much
+
+    *linesize_align = STRIDE_ALIGN;
+//STRIDE_ALIGN is 8 for SSE* but this does not work for SVQ1 chroma planes
+//we could change STRIDE_ALIGN to 16 for x86/sse but it would increase the
+//picture size unneccessarily in some cases. The solution here is not
+//pretty and better ideas are welcome!
+#if HAVE_MMX
+    if(s->codec_id == CODEC_ID_SVQ1 || s->codec_id == CODEC_ID_VP5 ||
+       s->codec_id == CODEC_ID_VP6 || s->codec_id == CODEC_ID_VP6F ||
+       s->codec_id == CODEC_ID_VP6A)
+        *linesize_align = 16;
+#endif
 }
 
+void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height){
+    int linesize_align;
+    avcodec_align_dimensions2(s, width, height, &linesize_align);
+    *width=FFALIGN(*width, 2*linesize_align);
+}
+
 int avcodec_check_dimensions(void *av_log_ctx, unsigned int w, unsigned int h){
     if((int)w>0 && (int)h>0 && (w+128)*(uint64_t)(h+128) < INT_MAX/8)
         return 0;
@@ -260 +278 @@
 
             unaligned = 0;
             for (i=0; i<4; i++){
-//STRIDE_ALIGN is 8 for SSE* but this does not work for SVQ1 chroma planes
-//we could change STRIDE_ALIGN to 16 for x86/sse but it would increase the
-//picture size unneccessarily in some cases. The solution here is not
-//pretty and better ideas are welcome!
-#if HAVE_MMX
-                if(s->codec_id == CODEC_ID_SVQ1 || s->codec_id == CODEC_ID_VP5 ||
-                   s->codec_id == CODEC_ID_VP6 || s->codec_id == CODEC_ID_VP6F ||
-                   s->codec_id == CODEC_ID_VP6A)
-                    stride_align[i]= 16;
-                else
-#endif
                 stride_align[i] = STRIDE_ALIGN;
                 unaligned |= picture.linesize[i] % stride_align[i];
             }

libavcodec/avcodec.h

@@ -1367 +1367 @@
     /**
      * Called at the beginning of each frame to get a buffer for it.
      * If pic.reference is set then the frame will be read later by libavcodec.
-     * avcodec_align_dimensions() should be used to find the required width and
+     * avcodec_align_dimensions2() should be used to find the required width and
      * height, as they normally need to be rounded up to the next multiple of 16.
      * if CODEC_CAP_DR1 is not set then get_buffer() must call
      * avcodec_default_get_buffer() instead of providing buffers allocated by
@@ -3226 +3226 @@
 int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic);
 void avcodec_default_release_buffer(AVCodecContext *s, AVFrame *pic);
 int avcodec_default_reget_buffer(AVCodecContext *s, AVFrame *pic);
+/**
+ * Modifies width and height values so that they will result in a memory
+ * buffer that is acceptable for the codec if you do not use any horizontal
+ * padding.
+ */
 void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height);
+/**
+ * Modifies width and height values so that they will result in a memory
+ * buffer that is acceptable for the codec if you also ensure that all
+ * line sizes are a multiple of linesize_align.
+ */
+void avcodec_align_dimensions2(AVCodecContext *s, int *width, int *height,
+                               int *linesize_align);
 
 /**
  * Checks if the given dimension of a picture is valid, meaning that all