* [FFmpeg-devel] [PATCH] avcodec/exrdec: restore applying color transfer characteristics for float16 samples
@ 2025-03-14 2:08 James Almer
0 siblings, 0 replies; only message in thread
From: James Almer @ 2025-03-14 2:08 UTC (permalink / raw)
To: ffmpeg-devel
Regression since 0e917389fe73c932049635d947bba076f1709589.
This change also reverts commit 431805c096738da7661a0baee2b12fe9724dcc95.
Signed-off-by: James Almer <jamrial@gmail.com>
---
libavcodec/exr.c | 38 ++++++++++++++++++++++++++++++++++++--
1 file changed, 36 insertions(+), 2 deletions(-)
diff --git a/libavcodec/exr.c b/libavcodec/exr.c
index 4482f104d0..107281e115 100644
--- a/libavcodec/exr.c
+++ b/libavcodec/exr.c
@@ -42,6 +42,7 @@
#include "libavutil/avstring.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
+#include "libavutil/float2half.h"
#include "libavutil/half2float.h"
#include "avcodec.h"
@@ -193,7 +194,10 @@ typedef struct EXRContext {
uint8_t *offset_table;
+ uint16_t gamma_table[65536];
+
Half2FloatTables h2f_tables;
+ Float2HalfTables f2h_tables;
} EXRContext;
static int zip_uncompress(const EXRContext *s, const uint8_t *src, int compressed_size,
@@ -1401,8 +1405,13 @@ static int decode_block(AVCodecContext *avctx, void *tdata,
}
} else if (s->pixel_type == EXR_HALF) {
// 16-bit
- for (int x = 0; x < xsize; x++, ptr_x += step)
- AV_WN16A(ptr_x, bytestream_get_le16(&src));
+ if (trc_func && (!c || (c < 3 && s->desc->flags & AV_PIX_FMT_FLAG_PLANAR))) {
+ for (int x = 0; x < xsize; x++, ptr_x += step)
+ AV_WN16A(ptr_x, s->gamma_table[bytestream_get_le16(&src)]);
+ } else {
+ for (int x = 0; x < xsize; x++, ptr_x += step)
+ AV_WN16A(ptr_x, bytestream_get_le16(&src));
+ }
}
// Zero out the end if xmax+1 is not w
@@ -2212,8 +2221,13 @@ static int decode_frame(AVCodecContext *avctx, AVFrame *picture,
static av_cold int decode_init(AVCodecContext *avctx)
{
EXRContext *s = avctx->priv_data;
+ uint32_t i;
+ union av_intfloat32 t;
+ float one_gamma = 1.0f / s->gamma;
+ av_csp_trc_function trc_func = NULL;
ff_init_half2float_tables(&s->h2f_tables);
+ ff_init_float2half_tables(&s->f2h_tables);
s->avctx = avctx;
@@ -2223,6 +2237,26 @@ static av_cold int decode_init(AVCodecContext *avctx)
ff_bswapdsp_init(&s->bbdsp);
#endif
+ trc_func = av_csp_trc_func_from_id(s->apply_trc_type);
+ if (trc_func) {
+ for (i = 0; i < 65536; ++i) {
+ t.i = half2float(i, &s->h2f_tables);
+ t.f = trc_func(t.f);
+ s->gamma_table[i] = float2half(av_float2int(t.f), &s->f2h_tables);
+ }
+ } else if (one_gamma != 1.0f) {
+ for (i = 0; i < 65536; ++i) {
+ t.i = half2float(i, &s->h2f_tables);
+ /* If negative value we reuse half value */
+ if (t.f <= 0.0f) {
+ s->gamma_table[i] = i;
+ } else {
+ t.f = powf(t.f, one_gamma);
+ s->gamma_table[i] = float2half(t.i, &s->f2h_tables);
+ }
+ }
+ }
+
// allocate thread data, used for non EXR_RAW compression types
s->thread_data = av_calloc(avctx->thread_count, sizeof(*s->thread_data));
if (!s->thread_data)
--
2.48.1
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2025-03-14 2:08 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2025-03-14 2:08 [FFmpeg-devel] [PATCH] avcodec/exrdec: restore applying color transfer characteristics for float16 samples James Almer
Git Inbox Mirror of the ffmpeg-devel mailing list - see https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
This inbox may be cloned and mirrored by anyone:
git clone --mirror https://master.gitmailbox.com/ffmpegdev/0 ffmpegdev/git/0.git
# If you have public-inbox 1.1+ installed, you may
# initialize and index your mirror using the following commands:
public-inbox-init -V2 ffmpegdev ffmpegdev/ https://master.gitmailbox.com/ffmpegdev \
ffmpegdev@gitmailbox.com
public-inbox-index ffmpegdev
Example config snippet for mirrors.
AGPL code for this site: git clone https://public-inbox.org/public-inbox.git