From 0a9cb385adb997238883787cf5b1f737462131d3 Mon Sep 17 00:00:00 2001 From: Sebastian Vater Date: Sat, 8 May 2010 21:48:44 +0000 Subject: Optimize decodeplane8(), patch by Sebastian Vater . Originally committed as revision 23061 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/iff.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 48 insertions(+), 7 deletions(-) (limited to 'libavcodec/iff.c') diff --git a/libavcodec/iff.c b/libavcodec/iff.c index 7189ac31cb..e563de1887 100644 --- a/libavcodec/iff.c +++ b/libavcodec/iff.c @@ -36,6 +36,49 @@ typedef struct { uint8_t * planebuf; } IffContext; +#define LUT8_PART(plane, v) \ + AV_LE2ME64C(UINT64_C(0x0000000)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1000000)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0010000)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1010000)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0000100)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1000100)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0010100)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1010100)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0000001)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1000001)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0010001)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1010001)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0000101)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1000101)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x0010101)<<32 | v) << plane, \ + AV_LE2ME64C(UINT64_C(0x1010101)<<32 | v) << plane + +#define LUT8(plane) { \ + LUT8_PART(plane, 0x0000000), \ + LUT8_PART(plane, 0x1000000), \ + LUT8_PART(plane, 0x0010000), \ + LUT8_PART(plane, 0x1010000), \ + LUT8_PART(plane, 0x0000100), \ + LUT8_PART(plane, 0x1000100), \ + LUT8_PART(plane, 0x0010100), \ + LUT8_PART(plane, 0x1010100), \ + LUT8_PART(plane, 0x0000001), \ + LUT8_PART(plane, 0x1000001), \ + LUT8_PART(plane, 0x0010001), \ + LUT8_PART(plane, 0x1010001), \ + LUT8_PART(plane, 0x0000101), \ + LUT8_PART(plane, 0x1000101), \ + LUT8_PART(plane, 0x0010101), \ + LUT8_PART(plane, 0x1010101), \ +} + +// 8 planes * 8-bit mask +static const uint64_t plane8_lut[8][256] = { + LUT8(0), LUT8(1), LUT8(2), LUT8(3), + LUT8(4), LUT8(5), LUT8(6), LUT8(7), +}; + /** * Convert CMAP buffer (stored in extradata) to lavc palette format */ @@ -95,14 +138,12 @@ static av_cold int decode_init(AVCodecContext *avctx) * @param bps bits_per_coded_sample (must be <= 8) * @param plane plane number to decode as */ -static void decodeplane8(uint8_t *dst, const uint8_t *const buf, int buf_size, int bps, int plane) +static void decodeplane8(uint8_t *dst, const uint8_t *buf, int buf_size, int bps, int plane) { - GetBitContext gb; - int i; - const int b = buf_size * 8; - init_get_bits(&gb, buf, buf_size * 8); - for(i = 0; i < b; i++) { - dst[i] |= get_bits1(&gb) << plane; + const uint64_t *lut = plane8_lut[plane]; + for(; --buf_size != 0; dst += 8) { + uint64_t v = AV_RN64A(dst) | lut[*buf++]; + AV_WN64A(dst, v); } } -- cgit v1.2.3