Fix bug caused by difference in stride and picture width.

When a frame is allocated using libschroedinger routines, the frame data size
does not match the actual frame size if the width is not a multiple of 16. So
we cannot do a straightforward memcpy of the frame returned by libschroedinger
into the FFmpeg picture as the stride differs from the width.

Fix this bug by allocating for the libschroedinger frame with the dimensions
in AVCodecContext within libavcodec and passing the frame to libschroedinger.

patch by Anuradha Suraparaju, anuradha rd.bbc.co uk

Originally committed as revision 19653 to svn://svn.ffmpeg.org/ffmpeg/trunk

4 files changed, 69 insertions, 14 deletions

diff --git a/libavcodec/libschroedinger.c b/libavcodec/libschroedinger.c
index ec9bde4880..242d354be3 100644
--- a/libavcodec/libschroedinger.c
+++ b/libavcodec/libschroedinger.c
@@ -77,3 +77,56 @@ int ff_get_schro_frame_format (SchroChromaFormat schro_pix_fmt,
     }
     return -1;
 }
+
+static void FreeSchroFrame(SchroFrame *frame, void *priv)
+{
+    AVPicture *p_pic = priv;
+
+    if (!p_pic)
+        return;
+
+    avpicture_free(p_pic);
+    av_freep(&p_pic);
+}
+
+SchroFrame *ff_create_schro_frame(AVCodecContext *avccontext,
+                                  SchroFrameFormat schro_frame_fmt)
+{
+    AVPicture *p_pic;
+    SchroFrame *p_frame;
+    int y_width, uv_width;
+    int y_height, uv_height;
+    int i;
+
+    y_width   = avccontext->width;
+    y_height  = avccontext->height;
+    uv_width  = y_width  >> (SCHRO_FRAME_FORMAT_H_SHIFT(schro_frame_fmt));
+    uv_height = y_height >> (SCHRO_FRAME_FORMAT_V_SHIFT(schro_frame_fmt));
+
+    p_pic = av_mallocz(sizeof(AVPicture));
+    avpicture_alloc(p_pic, avccontext->pix_fmt, y_width, y_height);
+
+    p_frame         = schro_frame_new();
+    p_frame->format = schro_frame_fmt;
+    p_frame->width  = y_width;
+    p_frame->height = y_height;
+    schro_frame_set_free_callback(p_frame, FreeSchroFrame, (void *)p_pic);
+
+    for (i = 0; i < 3; ++i) {
+        p_frame->components[i].width  = i ? uv_width : y_width;
+        p_frame->components[i].stride = p_pic->linesize[i];
+        p_frame->components[i].height = i ? uv_height : y_height;
+        p_frame->components[i].length =
+                 p_frame->components[i].stride * p_frame->components[i].height;
+        p_frame->components[i].data   = p_pic->data[i];
+
+        if (i) {
+            p_frame->components[i].v_shift =
+                SCHRO_FRAME_FORMAT_V_SHIFT(p_frame->format);
+            p_frame->components[i].h_shift =
+                SCHRO_FRAME_FORMAT_H_SHIFT(p_frame->format);
+        }
+    }
+
+    return p_frame;
+}
diff --git a/libavcodec/libschroedinger.h b/libavcodec/libschroedinger.h
index 71aa1b2251..cfc2087b47 100644
--- a/libavcodec/libschroedinger.h
+++ b/libavcodec/libschroedinger.h
@@ -53,4 +53,11 @@ SchroVideoFormatEnum ff_get_schro_video_format_preset (AVCodecContext *avccontex
 int ff_get_schro_frame_format(SchroChromaFormat schro_chroma_fmt,
                               SchroFrameFormat  *schro_frame_fmt);
 
+/**
+* Create a Schro frame based on the dimensions and frame format
+* passed. Returns a pointer to a frame on success, NULL on failure.
+*/
+SchroFrame *ff_create_schro_frame(AVCodecContext *avccontext,
+                                  SchroFrameFormat schro_frame_fmt);
+
 #endif /* AVCODEC_LIBSCHROEDINGER_H */
diff --git a/libavcodec/libschroedingerdec.c b/libavcodec/libschroedingerdec.c
index 02ee24bb92..53ded57ba4 100644
--- a/libavcodec/libschroedingerdec.c
+++ b/libavcodec/libschroedingerdec.c
@@ -256,11 +256,8 @@ static int libschroedinger_decode_frame(AVCodecContext *avccontext,
 
             case SCHRO_DECODER_NEED_FRAME:
                 /* Decoder needs a frame - create one and push it in. */
-
-                frame = schro_frame_new_and_alloc(NULL,
-                                                  p_schro_params->frame_format,
-                                                  format->width,
-                                                  format->height);
+                frame = ff_create_schro_frame(avccontext,
+                                              p_schro_params->frame_format);
                 schro_decoder_add_output_picture(decoder, frame);
                 break;
 
diff --git a/libavcodec/libschroedingerenc.c b/libavcodec/libschroedingerenc.c
index 94033cc256..9f8d95cc3e 100644
--- a/libavcodec/libschroedingerenc.c
+++ b/libavcodec/libschroedingerenc.c
@@ -223,15 +223,13 @@ static SchroFrame *libschroedinger_frame_from_data(AVCodecContext *avccontext,
     /* Input line size may differ from what the codec supports. Especially
      * when transcoding from one format to another. So use avpicture_layout
      * to copy the frame. */
-    in_frame = schro_frame_new_and_alloc(NULL,
-                                         p_schro_params->frame_format,
-                                         p_schro_params->format->width,
-                                         p_schro_params->format->height);
-
-    avpicture_layout((AVPicture *)in_data, avccontext->pix_fmt,
-                     avccontext->width, avccontext->height,
-                     in_frame->components[0].data,
-                     p_schro_params->frame_size);
+    in_frame = ff_create_schro_frame(avccontext, p_schro_params->frame_format);
+
+    if (in_frame)
+        avpicture_layout((AVPicture *)in_data, avccontext->pix_fmt,
+                          avccontext->width, avccontext->height,
+                          in_frame->components[0].data,
+                          p_schro_params->frame_size);
 
     return in_frame;
 }