diff mbox

[FFmpeg-devel] avformat/mp3dec: Fix definition of MIDDLE_BITS

Message ID 59d395ae.1adbbc15.bm000@wupperonline.de
State New
Headers show

Commit Message

Ingo Brückl Oct. 3, 2017, 1:50 p.m. UTC 
The number of bits from bit #m to #n is n - m plus 1.

Signed-off-by: Ingo Brückl <ib@wupperonline.de>
---
 libavformat/mp3dec.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--
2.14.2

Comments

Carl Eugen Hoyos Oct. 3, 2017, 9:14 p.m. UTC | #1 
2017-10-03 15:50 GMT+02:00 Ingo Brückl <ib@wupperonline.de>:
> The number of bits from bit #m to #n is n - m plus 1.

> -#define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m)))
> +#define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m) + 1))

I cannot comment on this patch but if this fixes a sample
of yours, please add a fate test.

Thank you, Carl Eugen
Michael Niedermayer Oct. 3, 2017, 11:59 p.m. UTC | #2 
On Tue, Oct 03, 2017 at 03:50:37PM +0200, Ingo Brückl wrote:
> The number of bits from bit #m to #n is n - m plus 1.
> 
> Signed-off-by: Ingo Brückl <ib@wupperonline.de>
> ---
>  libavformat/mp3dec.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

will apply patch

thanks

[...]
diff mbox

Patch

diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c
index 0924a57843..a5c4f2ea12 100644
--- a/libavformat/mp3dec.c
+++ b/libavformat/mp3dec.c
@@ -142,7 +142,7 @@  static void mp3_parse_info_tag(AVFormatContext *s, AVStream *st,
                                MPADecodeHeader *c, uint32_t spf)
 {
 #define LAST_BITS(k, n) ((k) & ((1 << (n)) - 1))
-#define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m)))
+#define MIDDLE_BITS(k, m, n) LAST_BITS((k) >> (m), ((n) - (m) + 1))

     uint16_t crc;
     uint32_t v;