From 0f6931f4b60cf1e65fd9a5da791c8ee913053f52 Mon Sep 17 00:00:00 2001 From: Benoit Fouet Date: Wed, 3 Dec 2014 14:31:28 +0100 Subject: [PATCH] avcodec/pngdec: use memcpy instead of byte loops for P frames. Rely on the way memcpy is optimized for one's system instead of looping on a byte buffer for buffer copies to handle P frames. Tested-by: Christophe Gisquet Signed-off-by: Michael Niedermayer --- libavcodec/pngdec.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-) diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c index 7e7b2858b3..e6b759322c 100644 --- a/libavcodec/pngdec.c +++ b/libavcodec/pngdec.c @@ -884,8 +884,7 @@ static int handle_p_frame_apng(AVCodecContext *avctx, PNGDecContext *s, ff_thread_await_progress(&s->previous_picture, INT_MAX, 0); for (j = 0; j < s->y_offset; j++) { - for (i = 0; i < ls; i++) - pd[i] = pd_last[i]; + memcpy(pd, pd_last, ls); pd += s->image_linesize; pd_last += s->image_linesize; } @@ -907,8 +906,9 @@ static int handle_p_frame_apng(AVCodecContext *avctx, PNGDecContext *s, } for (j = s->y_offset; j < s->y_offset + s->cur_h; j++) { - for (i = 0; i < s->x_offset * s->bpp; i++) - pd[i] = pd_last[i]; + i = s->x_offset * s->bpp; + if (i) + memcpy(pd, pd_last, i); for (; i < (s->x_offset + s->cur_w) * s->bpp; i += s->bpp) { uint8_t alpha = pd[i+ai]; @@ -930,26 +930,27 @@ static int handle_p_frame_apng(AVCodecContext *avctx, PNGDecContext *s, break; } } - for (; i < ls; i++) - pd[i] = pd_last[i]; + if (ls - i) + memcpy(pd+i, pd_last+i, ls - i); pd += s->image_linesize; pd_last += s->image_linesize; pd_last_region += s->image_linesize; } } else { for (j = s->y_offset; j < s->y_offset + s->cur_h; j++) { - for (i = 0; i < s->x_offset * s->bpp; i++) - pd[i] = pd_last[i]; - for (i = (s->x_offset + s->cur_w) * s->bpp; i < ls; i++) - pd[i] = pd_last[i]; + int end_offset = (s->x_offset + s->cur_w) * s->bpp; + int end_len = ls - end_offset; + if (s->x_offset) + memcpy(pd, pd_last, s->x_offset * s->bpp); + if (end_len) + memcpy(pd+end_offset, pd_last+end_offset, end_len); pd += s->image_linesize; pd_last += s->image_linesize; } } for (j = s->y_offset + s->cur_h; j < s->height; j++) { - for (i = 0; i < ls; i++) - pd[i] = pd_last[i]; + memcpy(pd, pd_last, ls); pd += s->image_linesize; pd_last += s->image_linesize; }