diff options
| -rw-r--r-- | libavcodec/vorbis.c | 38 |
1 files changed, 32 insertions, 6 deletions
diff --git a/libavcodec/vorbis.c b/libavcodec/vorbis.c index fd0cafa187..f89be252c5 100644 --- a/libavcodec/vorbis.c +++ b/libavcodec/vorbis.c @@ -146,25 +146,51 @@ void ff_vorbis_ready_floor1_list(vorbis_floor1_entry * list, int values) { } } +static inline void render_line_unrolled(intptr_t x, intptr_t y, int x1, intptr_t sy, int ady, int adx, float * buf) { + int err = -adx; + int tmp; + x -= x1-1; + buf += x1-1; + while (++x < 0) { + err += ady; + if (err >= 0) { + err += ady - adx; + y += sy; + buf[x++] = ff_vorbis_floor1_inverse_db_table[y]; + } + buf[x] = ff_vorbis_floor1_inverse_db_table[y]; + } + if (x <= 0) { + if (err + ady >= 0) + y += sy; + buf[x] = ff_vorbis_floor1_inverse_db_table[y]; + } +} + static void render_line(int x0, int y0, int x1, int y1, float * buf) { int dy = y1 - y0; int adx = x1 - x0; + int ady = FFABS(dy); + int sy = dy<0 ? -1 : 1; + buf[x0] = ff_vorbis_floor1_inverse_db_table[y0]; + if(ady*2<=adx) { // optimized common case + render_line_unrolled(x0, y0, x1, sy, ady, adx, buf); + } else { int base = dy / adx; - int ady = FFABS(dy) - FFABS(base) * adx; int x = x0; int y = y0; - int err = 0; - int sy = dy<0 ? -1 : 1; - buf[x] = ff_vorbis_floor1_inverse_db_table[y]; + int err = -adx; + ady -= FFABS(base) * adx; while (++x < x1) { + y += base; err += ady; - if (err >= adx) { + if (err >= 0) { err -= adx; y += sy; } - y += base; buf[x] = ff_vorbis_floor1_inverse_db_table[y]; } + } } void ff_vorbis_floor1_render_list(vorbis_floor1_entry * list, int values, uint_fast16_t * y_list, int * flag, int multiplier, float * out, int samples) { |