[FFmpeg-cvslog] avfilter/vf_histogram: fix segfault in parade waveform mode for subsampled formats

[Marton Balint]

ffmpeg | branch: master | Marton Balint <cus at passwd.hu> | Wed Oct  2 22:23:54 2013 +0200| [5b5bb0d81c5353f64e142a52ade18db4a6c2f512] | committer: Paul B Mahol

avfilter/vf_histogram: fix segfault in parade waveform mode for subsampled formats

Signed-off-by: Marton Balint <cus at passwd.hu>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=5b5bb0d81c5353f64e142a52ade18db4a6c2f512
---

 libavfilter/vf_histogram.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/libavfilter/vf_histogram.c b/libavfilter/vf_histogram.c
index 273d03b..4bd309f 100644
--- a/libavfilter/vf_histogram.c
+++ b/libavfilter/vf_histogram.c
@@ -183,15 +183,15 @@ static void gen_waveform(HistogramContext *h, AVFrame *inpicref, AVFrame *outpic
                          int component, int intensity, int offset, int col_mode)
 {
     const int plane = h->desc->comp[component].plane;
+    const int is_chroma = (component == 1 || component == 2);
+    const int shift_w = (is_chroma ? h->desc->log2_chroma_w : 0);
+    const int shift_h = (is_chroma ? h->desc->log2_chroma_h : 0);
     const int src_linesize = inpicref->linesize[plane];
     const int dst_linesize = outpicref->linesize[plane];
     uint8_t *src_data = inpicref->data[plane];
-    uint8_t *dst_data = outpicref->data[plane] + (col_mode ? offset * dst_linesize : offset);
+    uint8_t *dst_data = outpicref->data[plane] + (col_mode ? (offset >> shift_h) * dst_linesize : offset >> shift_w);
     uint8_t * const dst_line = dst_data;
     const uint8_t max = 255 - intensity;
-    const int is_chroma = (component == 1 || component == 2);
-    const int shift_w = (is_chroma ? h->desc->log2_chroma_w : 0);
-    const int shift_h = (is_chroma ? h->desc->log2_chroma_h : 0);
     const int src_h = FF_CEIL_RSHIFT(inpicref->height, shift_h);
     const int src_w = FF_CEIL_RSHIFT(inpicref->width, shift_w);
     uint8_t *dst, *p;