On 09/09/18 23:08, Mark Thompson wrote:
> Adds an option to specify the number of tile rows and columns, then uses
> equal-sized tiles to fill the frame.
> ---
> Useful for testing to make arbitrary arrangements of tiles, though the
> requirement to set the superblock size for the whole stream at the top level
> rather than letting it be set dynamically is slightly unfortunate.
>
> The rounding error is placed at the left/top here, it might be better to
> place it around the sides instead? (The most important detail is likely to
> be in the centre of the frame, so make the tiles there smaller? I'm not sure
> whether this argument is actually valid, though.)
>
>
> libavcodec/libaomenc.c | 55 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 55 insertions(+)
>
> diff --git a/libavcodec/libaomenc.c b/libavcodec/libaomenc.c
> index 9431179886..0b4fa71fc7 100644
> --- a/libavcodec/libaomenc.c
> +++ b/libavcodec/libaomenc.c
> ...
> @@ -431,6 +438,51 @@ static av_cold int aom_init(AVCodecContext *avctx,
>
> enccfg.g_error_resilient = ctx->error_resilient;
>
> + if (ctx->tile_cols && ctx->tile_rows) {
> + int sb_size, sb_width, sb_height;
> + int cols_per_tile, cols_step, rows_per_tile, rows_step, i;
> +
> + if (avctx->width / ctx->tile_cols < 128 ||
> + avctx->width / ctx->tile_rows < 128) {
avctx->height for the second test, of course.
There could be some rounding here too, though I'm not sure what the 128x128 vs.
64x64 tradeoff actually involves - if the frame is very small do we want the
largest superblock size?
> + // User has requested more tiles than would fit with 128x128
> + // superblocks, so assume they want 64x64.
> + sb_size = 64;
> + superblock_size = AOM_SUPERBLOCK_SIZE_64X64;
> + } else {
> + sb_size = 128;
> + superblock_size = AOM_SUPERBLOCK_SIZE_128X128;
> + }
> +
> + if (avctx->width / ctx->tile_cols < sb_size ||
> + avctx->height / ctx->tile_rows < sb_size) {
This should probably be rounded with the test the other way:
+ if ((avctx->width + sb_size - 1) / sb_size < ctx->tile_cols ||
+ (avctx->height + sb_size - 1) / sb_size < ctx->tile_rows) {
> + av_log(avctx, AV_LOG_ERROR, "Invalid tile sizing: tiles must be "
> + "at least one superblock wide and high.\n");
> + return AVERROR(EINVAL);
> + }
> + if (ctx->tile_cols > MAX_TILE_WIDTHS ||
> + ctx->tile_rows > MAX_TILE_HEIGHTS) {
> + av_log(avctx, AV_LOG_ERROR, "Invalid tile sizing: at most %dx%d "
> + "tiles allowed.\n", MAX_TILE_WIDTHS, MAX_TILE_HEIGHTS);
> + return AVERROR(EINVAL);
> + }
> +
> + enccfg.tile_width_count = ctx->tile_cols;
> + enccfg.tile_height_count = ctx->tile_rows;
> +
> + sb_width = (avctx->width + sb_size - 1) / sb_size;
> + sb_height = (avctx->height + sb_size - 1) / sb_size;
> +
> + cols_per_tile = sb_width / ctx->tile_cols;
> + cols_step = sb_width % ctx->tile_cols;
> + for (i = 0; i < ctx->tile_cols; i++)
> + enccfg.tile_widths[i] = cols_per_tile + (i < cols_step);
> +
> + rows_per_tile = sb_height / ctx->tile_rows;
> + rows_step = sb_height % ctx->tile_rows;
> + for (i = 0; i < ctx->tile_rows; i++)
> + enccfg.tile_heights[i] = rows_per_tile + (i < rows_step);
> + }
> ...
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
