[FFmpeg-devel] [PATCH v2 3/3] avcodec/exr: use luma+alpha float pixel formats
Andreas Rheinhardt
andreas.rheinhardt at outlook.com
Wed Mar 5 23:41:40 EET 2025
James Almer:
> Signed-off-by: James Almer <jamrial at gmail.com>
> ---
> Updated for the latest git master changes.
>
> libavcodec/exr.c | 55 ++++++++------------
> tests/ref/fate/exr-ya-scanline-zip-half-12x8 | 2 +-
> 2 files changed, 22 insertions(+), 35 deletions(-)
>
> diff --git a/libavcodec/exr.c b/libavcodec/exr.c
> index b25e9ef397..fe5f62c3b5 100644
> --- a/libavcodec/exr.c
> +++ b/libavcodec/exr.c
> @@ -1352,33 +1352,32 @@ static int decode_block(AVCodecContext *avctx, void *tdata,
> data_yoffset = FFABS(FFMIN(0, line));
> data_window_offset = (data_yoffset * td->channel_line_size) + data_xoffset;
>
> + if (s->channel_offsets[3] >= 0)
> + channel_buffer[3] = src + (td->xsize * s->channel_offsets[3]) + data_window_offset;
> if (!s->is_luma) {
> channel_buffer[0] = src + (td->xsize * s->channel_offsets[0]) + data_window_offset;
> channel_buffer[1] = src + (td->xsize * s->channel_offsets[1]) + data_window_offset;
> channel_buffer[2] = src + (td->xsize * s->channel_offsets[2]) + data_window_offset;
> rgb_channel_count = 3;
> - } else { /* put y data in the first channel_buffer */
> + } else { /* put y data in the first channel_buffer and if needed, alpha in the second */
> channel_buffer[0] = src + (td->xsize * s->channel_offsets[1]) + data_window_offset;
> + if (!(s->desc->flags & AV_PIX_FMT_FLAG_PLANAR))
> + channel_buffer[1] = channel_buffer[3];
> rgb_channel_count = 1;
> }
> - if (s->channel_offsets[3] >= 0)
> - channel_buffer[3] = src + (td->xsize * s->channel_offsets[3]) + data_window_offset;
> -
> - if (s->desc->flags & AV_PIX_FMT_FLAG_PLANAR || s->desc->nb_components == 1 ) {
> - /* todo: change this when a floating point pixel format with luma with alpha is implemented */
> - int channel_count = s->channel_offsets[3] >= 0 ? 4 : rgb_channel_count;
> - if (s->is_luma) {
> - channel_buffer[1] = channel_buffer[0];
> - channel_buffer[2] = channel_buffer[0];
> - }
>
> - for (c = 0; c < channel_count; c++) {
> + if (s->desc->flags & AV_PIX_FMT_FLAG_FLOAT) {
> + for (c = 0; c < s->desc->nb_components; c++) {
> int plane = s->desc->comp[c].plane;
> - ptr = p->data[plane] + window_ymin * p->linesize[plane] + (window_xmin * step);
> + ptr = p->data[plane] + window_ymin * p->linesize[plane] + (window_xmin * step) + s->desc->comp[c].offset;
>
> for (i = 0; i < ysize; i++, ptr += p->linesize[plane]) {
> const uint8_t *src;
>
> + // Zero out the start if xmin is not 0
> + if (s->desc->flags & AV_PIX_FMT_FLAG_PLANAR || !c)
> + memset(ptr, 0, bxmin);
> +
> if (s->pixel_type == EXR_FLOAT ||
> s->compression == EXR_DWAA ||
> s->compression == EXR_DWAB) {
> @@ -1387,42 +1386,36 @@ static int decode_block(AVCodecContext *avctx, void *tdata,
>
> src = channel_buffer[c];
>
> - // Zero out the start if xmin is not 0
> - memset(ptr_x, 0, bxmin);
> - ptr_x += 4 * window_xoffset;
> + ptr_x += window_xoffset * step;
>
> if (trc_func && c < 3) {
> - for (int x = 0; x < xsize; x++, ptr_x += 4) {
> + for (x = 0; x < xsize; x++, ptr_x += step) {
> float f = av_int2float(bytestream_get_le32(&src));
> AV_WN32A(ptr_x, av_float2int(trc_func(f)));
> }
> } else if (one_gamma != 1.f) {
> - for (int x = 0; x < xsize; x++, ptr_x += 4) {
> + for (x = 0; x < xsize; x++, ptr_x += step) {
> float f = av_int2float(bytestream_get_le32(&src));
> if (f > 0.0f && c < 3) /* avoid negative values */
> f = powf(f, one_gamma);
> AV_WN32A(ptr_x, av_float2int(f));
> }
> } else {
> - for (int x = 0; x < xsize; x++, ptr_x += 4)
> + for (x = 0; x < xsize; x++, ptr_x += step)
Don't remove loop-scope for iterators.
> AV_WN32A(ptr_x, bytestream_get_le32(&src));
> }
> - memset(ptr_x, 0, axmax);
> } else if (s->pixel_type == EXR_HALF) {
> src = channel_buffer[c];
>
> - // Zero out the start if xmin is not 0
> - memset(ptr, 0, bxmin);
> -
> // 16-bit
> for (x = window_xoffset; x < xsize + window_xoffset; x++) {
> int v = bytestream_get_le16(&src);
> - AV_WN16(ptr + x * sizeof(uint16_t), v);
> + AV_WN16(ptr + x * step, v);
What values can step have here?
> }
> - memset(ptr + x * sizeof(uint16_t), 0, axmax);
> }
>
> // Zero out the end if xmax+1 is not w
> + memset(ptr + x * step, 0, axmax);
> channel_buffer[c] += td->channel_line_size;
> }
> }
> @@ -2054,8 +2047,7 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *picture,
> if (!s->is_luma) {
> avctx->pix_fmt = AV_PIX_FMT_GBRAPF16;
> } else {
> - /* todo: change this when a floating point pixel format with luma with alpha is implemented */
> - avctx->pix_fmt = AV_PIX_FMT_GBRAPF16;
> + avctx->pix_fmt = AV_PIX_FMT_YAF16;
> }
> } else {
> if (!s->is_luma) {
> @@ -2071,8 +2063,7 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *picture,
> if (!s->is_luma) {
> avctx->pix_fmt = AV_PIX_FMT_GBRAPF32;
> } else {
> - /* todo: change this when a floating point pixel format with luma with alpha is implemented */
> - avctx->pix_fmt = AV_PIX_FMT_GBRAPF32;
> + avctx->pix_fmt = AV_PIX_FMT_YAF32;
> }
> } else {
> if (!s->is_luma) {
> @@ -2151,11 +2142,7 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *picture,
> if (!s->desc)
> return AVERROR_INVALIDDATA;
>
> - if (s->desc->flags & AV_PIX_FMT_FLAG_PLANAR) {
> - planes = s->desc->nb_components;
> - } else {
> - planes = 1;
> - }
> + planes = av_pix_fmt_count_planes(avctx->pix_fmt);
> out_line_size = avctx->width * s->desc->comp[0].step;
>
> if (s->is_tile) {
> diff --git a/tests/ref/fate/exr-ya-scanline-zip-half-12x8 b/tests/ref/fate/exr-ya-scanline-zip-half-12x8
> index 97ea715962..6c07f19846 100644
> --- a/tests/ref/fate/exr-ya-scanline-zip-half-12x8
> +++ b/tests/ref/fate/exr-ya-scanline-zip-half-12x8
> @@ -3,4 +3,4 @@
> #codec_id 0: rawvideo
> #dimensions 0: 12x8
> #sar 0: 1/1
> -0, 0, 0, 1, 1536, 0x2b457bd2
> +0, 0, 0, 1, 1536, 0xa33f5f69
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