diff mbox

[FFmpeg-devel] avcodec/cbs_mpeg2: use memcpy when assembling fragments

Message ID 20180424023954.12176-1-jamrial@gmail.com
State Accepted
Commit 0161d91db01ae0b5d516232d92764f5a898cedc6
Headers show

Commit Message

James Almer April 24, 2018, 2:39 a.m. UTC 
before:
419022 decicycles in assemble_fragment,    2047 runs,      1 skips

after:
104621 decicycles in assemble_fragment,    2045 runs,      3 skips

Benched with a 2 minutes long 720x480 DVD mpeg2 sample.

Signed-off-by: James Almer <jamrial@gmail.com>
---
 libavcodec/cbs_mpeg2.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Michael Niedermayer April 25, 2018, 7:35 p.m. UTC | #1 
On Mon, Apr 23, 2018 at 11:39:54PM -0300, James Almer wrote:
> before:
> 419022 decicycles in assemble_fragment,    2047 runs,      1 skips
> 
> after:
> 104621 decicycles in assemble_fragment,    2045 runs,      3 skips
> 
> Benched with a 2 minutes long 720x480 DVD mpeg2 sample.
> 
> Signed-off-by: James Almer <jamrial@gmail.com>
> ---
>  libavcodec/cbs_mpeg2.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

LGTM
thx

[...]
James Almer April 25, 2018, 7:51 p.m. UTC | #2 
On 4/25/2018 4:35 PM, Michael Niedermayer wrote:
> On Mon, Apr 23, 2018 at 11:39:54PM -0300, James Almer wrote:
>> before:
>> 419022 decicycles in assemble_fragment,    2047 runs,      1 skips
>>
>> after:
>> 104621 decicycles in assemble_fragment,    2045 runs,      3 skips
>>
>> Benched with a 2 minutes long 720x480 DVD mpeg2 sample.
>>
>> Signed-off-by: James Almer <jamrial@gmail.com>
>> ---
>>  libavcodec/cbs_mpeg2.c | 6 +++---
>>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> LGTM
> thx

Pushed, thanks.
diff mbox

Patch

diff --git a/libavcodec/cbs_mpeg2.c b/libavcodec/cbs_mpeg2.c
index bfb64a0851..94b9591b21 100644
--- a/libavcodec/cbs_mpeg2.c
+++ b/libavcodec/cbs_mpeg2.c
@@ -362,7 +362,7 @@  static int cbs_mpeg2_assemble_fragment(CodedBitstreamContext *ctx,
                                        CodedBitstreamFragment *frag)
 {
     uint8_t *data;
-    size_t size, dp, sp;
+    size_t size, dp;
     int i;
 
     size = 0;
@@ -382,8 +382,8 @@  static int cbs_mpeg2_assemble_fragment(CodedBitstreamContext *ctx,
         data[dp++] = 0;
         data[dp++] = 1;
 
-        for (sp = 0; sp < unit->data_size; sp++)
-            data[dp++] = unit->data[sp];
+        memcpy(data + dp, unit->data, unit->data_size);
+        dp += unit->data_size;
     }
 
     av_assert0(dp == size);