diff options
author | Tom Butterworth <bangnoise@gmail.com> | 2015-07-23 02:03:29 +0300 |
---|---|---|
committer | Luca Barbato <lu_zero@gentoo.org> | 2015-07-23 11:45:40 +0300 |
commit | ebe8b5d947c41449c684f17c6826fe6bc46c0360 (patch) | |
tree | 7f6f279f848cf1c2fc6f8ecf6f328a8a0f0a94c5 /libavcodec | |
parent | 22ecfcd4c79cdf812fdf406525ddf0fd1f7114e4 (diff) |
dds: Fix the slice size computation
A bug was introduced in 6b2b26e7af3ede0abfb46eb5725c26d1083f50bc whereby when
frame height wasn't divisible by the number of threads, pixels would be omitted
from the bottom rows during decode.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Diffstat (limited to 'libavcodec')
-rw-r--r-- | libavcodec/dds.c | 26 |
1 files changed, 17 insertions, 9 deletions
diff --git a/libavcodec/dds.c b/libavcodec/dds.c index 625cb3027d..2c3a2f25b8 100644 --- a/libavcodec/dds.c +++ b/libavcodec/dds.c @@ -105,7 +105,7 @@ typedef struct DDSContext { const uint8_t *tex_data; // Compressed texture int tex_ratio; // Compression ratio - int slice_size; // Optimal slice size + int slice_count; // Number of slices for threaded operations /* Pointer to the selected compress or decompress function. */ int (*tex_funct)(uint8_t *dst, ptrdiff_t stride, const uint8_t *block); @@ -421,14 +421,23 @@ static int decompress_texture_thread(AVCodecContext *avctx, void *arg, AVFrame *frame = arg; const uint8_t *d = ctx->tex_data; int w_block = avctx->coded_width / TEXTURE_BLOCK_W; + int h_block = avctx->coded_height / TEXTURE_BLOCK_H; int x, y; int start_slice, end_slice; + int base_blocks_per_slice = h_block / ctx->slice_count; + int remainder_blocks = h_block % ctx->slice_count; - start_slice = slice * ctx->slice_size; - end_slice = FFMIN(start_slice + ctx->slice_size, avctx->coded_height); + /* When the frame height (in blocks) doesn't divide evenly between the + * number of slices, spread the remaining blocks evenly between the first + * operations */ + start_slice = slice * base_blocks_per_slice; + /* Add any extra blocks (one per slice) that have been added before this slice */ + start_slice += FFMIN(slice, remainder_blocks); - start_slice /= TEXTURE_BLOCK_H; - end_slice /= TEXTURE_BLOCK_H; + end_slice = start_slice + base_blocks_per_slice; + /* Add an extra block if there are still remainder blocks to be accounted for */ + if (slice < remainder_blocks) + end_slice++; for (y = start_slice; y < end_slice; y++) { uint8_t *p = frame->data[0] + y * frame->linesize[0] * TEXTURE_BLOCK_H; @@ -633,13 +642,12 @@ static int dds_decode(AVCodecContext *avctx, void *data, return ret; if (ctx->compressed) { - int slices = FFMIN(avctx->thread_count, - avctx->coded_height / TEXTURE_BLOCK_H); - ctx->slice_size = avctx->coded_height / slices; + ctx->slice_count = av_clip(avctx->thread_count, 1, + avctx->coded_height / TEXTURE_BLOCK_H); /* Use the decompress function on the texture, one block per thread. */ ctx->tex_data = gbc->buffer; - avctx->execute2(avctx, decompress_texture_thread, frame, NULL, slices); + avctx->execute2(avctx, decompress_texture_thread, frame, NULL, ctx->slice_count); } else { int linesize = av_image_get_linesize(avctx->pix_fmt, frame->width, 0); |