[FFmpeg-cvslog] avcodec/pngdec: read colorspace info when decoding with AVDISCARD_ALL
Leo Izen
git at videolan.org
Tue Feb 28 21:45:27 EET 2023
ffmpeg | branch: master | Leo Izen <leo.izen at gmail.com> | Thu Feb 2 10:01:42 2023 -0500| [fadfa147f812a3fe9e68723347d37b9cccd6222d] | committer: Leo Izen
avcodec/pngdec: read colorspace info when decoding with AVDISCARD_ALL
These chunks are lightweight and it's useful information to have when
running ffmpeg -i or ffprobe, for example.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fadfa147f812a3fe9e68723347d37b9cccd6222d
---
libavcodec/pngdec.c | 136 +++++++++++++++++++++++++++----------------
tests/ref/fate/png-icc | 8 +--
tests/ref/fate/png-side-data | 2 +-
3 files changed, 91 insertions(+), 55 deletions(-)
diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index d63640345b..9403d72f2f 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -75,6 +75,7 @@ typedef struct PNGDecContext {
int have_chrm;
uint32_t white_point[2];
uint32_t display_primaries[3][2];
+ int gamma;
int have_srgb;
int have_cicp;
enum AVColorPrimaries cicp_primaries;
@@ -641,6 +642,83 @@ static int decode_phys_chunk(AVCodecContext *avctx, PNGDecContext *s,
return 0;
}
+/*
+ * This populates AVCodecContext fields so it must be called before
+ * ff_thread_finish_setup() to avoid a race condition with respect to the
+ * generic copying of avctx fields.
+ */
+static int populate_avctx_color_fields(AVCodecContext *avctx, AVFrame *frame)
+{
+ PNGDecContext *s = avctx->priv_data;
+
+ if (s->have_cicp) {
+ if (s->cicp_primaries >= AVCOL_PRI_NB)
+ av_log(avctx, AV_LOG_WARNING, "unrecognized cICP primaries\n");
+ else
+ avctx->color_primaries = frame->color_primaries = s->cicp_primaries;
+ if (s->cicp_trc >= AVCOL_TRC_NB)
+ av_log(avctx, AV_LOG_WARNING, "unrecognized cICP transfer\n");
+ else
+ avctx->color_trc = frame->color_trc = s->cicp_trc;
+ if (s->cicp_range == 0)
+ av_log(avctx, AV_LOG_WARNING, "unsupported tv-range cICP chunk\n");
+ } else if (s->iccp_data) {
+ AVFrameSideData *sd = av_frame_new_side_data(frame, AV_FRAME_DATA_ICC_PROFILE, s->iccp_data_len);
+ if (!sd)
+ return AVERROR(ENOMEM);
+ memcpy(sd->data, s->iccp_data, s->iccp_data_len);
+ av_dict_set(&sd->metadata, "name", s->iccp_name, 0);
+ } else if (s->have_srgb) {
+ avctx->color_primaries = frame->color_primaries = AVCOL_PRI_BT709;
+ avctx->color_trc = frame->color_trc = AVCOL_TRC_IEC61966_2_1;
+ } else if (s->have_chrm) {
+ AVColorPrimariesDesc desc;
+ enum AVColorPrimaries prim;
+ desc.wp.x = av_make_q(s->white_point[0], 100000);
+ desc.wp.y = av_make_q(s->white_point[1], 100000);
+ desc.prim.r.x = av_make_q(s->display_primaries[0][0], 100000);
+ desc.prim.r.y = av_make_q(s->display_primaries[0][1], 100000);
+ desc.prim.g.x = av_make_q(s->display_primaries[1][0], 100000);
+ desc.prim.g.y = av_make_q(s->display_primaries[1][1], 100000);
+ desc.prim.b.x = av_make_q(s->display_primaries[2][0], 100000);
+ desc.prim.b.y = av_make_q(s->display_primaries[2][1], 100000);
+ prim = av_csp_primaries_id_from_desc(&desc);
+ if (prim != AVCOL_PRI_UNSPECIFIED)
+ avctx->color_primaries = frame->color_primaries = prim;
+ else
+ av_log(avctx, AV_LOG_WARNING, "unknown cHRM primaries\n");
+ }
+
+ /* these chunks override gAMA */
+ if (s->iccp_data || s->have_srgb || s->have_cicp) {
+ av_dict_set(&s->frame_metadata, "gamma", NULL, 0);
+ } else if (s->gamma) {
+ /*
+ * These values are 100000/2.2, 100000/2.8, 100000/2.6, and
+ * 100000/1.0 respectively. 45455, 35714, and 38462, and 100000.
+ * There's a 0.001 gamma tolerance here in case of floating
+ * point issues when the PNG was written.
+ *
+ * None of the other enums have a pure gamma curve so it makes
+ * sense to leave those to sRGB and cICP.
+ */
+ if (s->gamma > 45355 && s->gamma < 45555)
+ avctx->color_trc = frame->color_trc = AVCOL_TRC_GAMMA22;
+ else if (s->gamma > 35614 && s->gamma < 35814)
+ avctx->color_trc = frame->color_trc = AVCOL_TRC_GAMMA28;
+ else if (s->gamma > 38362 && s->gamma < 38562)
+ avctx->color_trc = frame->color_trc = AVCOL_TRC_SMPTE428;
+ else if (s->gamma > 99900 && s->gamma < 100100)
+ avctx->color_trc = frame->color_trc = AVCOL_TRC_LINEAR;
+ }
+
+ /* we only support pc-range RGB */
+ avctx->colorspace = frame->colorspace = AVCOL_SPC_RGB;
+ avctx->color_range = frame->color_range = AVCOL_RANGE_JPEG;
+
+ return 0;
+}
+
static int decode_idat_chunk(AVCodecContext *avctx, PNGDecContext *s,
GetByteContext *gb, AVFrame *p)
{
@@ -756,6 +834,8 @@ static int decode_idat_chunk(AVCodecContext *avctx, PNGDecContext *s,
p->key_frame = 1;
p->interlaced_frame = !!s->interlace_type;
+ if ((ret = populate_avctx_color_fields(avctx, p)) < 0)
+ return ret;
ff_thread_finish_setup(avctx);
/* compute the compressed row size */
@@ -1257,6 +1337,10 @@ static int decode_frame_common(AVCodecContext *avctx, PNGDecContext *s,
case MKTAG('t', 'E', 'X', 't'):
case MKTAG('I', 'D', 'A', 'T'):
case MKTAG('t', 'R', 'N', 'S'):
+ case MKTAG('s', 'R', 'G', 'B'):
+ case MKTAG('c', 'I', 'C', 'P'):
+ case MKTAG('c', 'H', 'R', 'M'):
+ case MKTAG('g', 'A', 'M', 'A'):
break;
default:
continue;
@@ -1359,10 +1443,10 @@ static int decode_frame_common(AVCodecContext *avctx, PNGDecContext *s,
case MKTAG('g', 'A', 'M', 'A'): {
AVBPrint bp;
char *gamma_str;
- int num = bytestream2_get_be32(&gb_chunk);
+ s->gamma = bytestream2_get_be32(&gb_chunk);
av_bprint_init(&bp, 0, AV_BPRINT_SIZE_UNLIMITED);
- av_bprintf(&bp, "%i/%i", num, 100000);
+ av_bprintf(&bp, "%i/%i", s->gamma, 100000);
ret = av_bprint_finalize(&bp, &gamma_str);
if (ret < 0)
return ret;
@@ -1500,56 +1584,8 @@ static void clear_frame_metadata(PNGDecContext *s)
static int output_frame(PNGDecContext *s, AVFrame *f)
{
- AVCodecContext *avctx = s->avctx;
int ret;
- if (s->have_cicp) {
- if (s->cicp_primaries >= AVCOL_PRI_NB)
- av_log(avctx, AV_LOG_WARNING, "unrecognized cICP primaries\n");
- else
- avctx->color_primaries = f->color_primaries = s->cicp_primaries;
- if (s->cicp_trc >= AVCOL_TRC_NB)
- av_log(avctx, AV_LOG_WARNING, "unrecognized cICP transfer\n");
- else
- avctx->color_trc = f->color_trc = s->cicp_trc;
- avctx->color_range = f->color_range =
- s->cicp_range == 0 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
- } else if (s->iccp_data) {
- AVFrameSideData *sd = av_frame_new_side_data(f, AV_FRAME_DATA_ICC_PROFILE, s->iccp_data_len);
- if (!sd) {
- ret = AVERROR(ENOMEM);
- goto fail;
- }
- memcpy(sd->data, s->iccp_data, s->iccp_data_len);
-
- av_dict_set(&sd->metadata, "name", s->iccp_name, 0);
- } else if (s->have_srgb) {
- avctx->color_primaries = f->color_primaries = AVCOL_PRI_BT709;
- avctx->color_trc = f->color_trc = AVCOL_TRC_IEC61966_2_1;
- } else if (s->have_chrm) {
- AVColorPrimariesDesc desc;
- enum AVColorPrimaries prim;
- desc.wp.x = av_make_q(s->white_point[0], 100000);
- desc.wp.y = av_make_q(s->white_point[1], 100000);
- desc.prim.r.x = av_make_q(s->display_primaries[0][0], 100000);
- desc.prim.r.y = av_make_q(s->display_primaries[0][1], 100000);
- desc.prim.g.x = av_make_q(s->display_primaries[1][0], 100000);
- desc.prim.g.y = av_make_q(s->display_primaries[1][1], 100000);
- desc.prim.b.x = av_make_q(s->display_primaries[2][0], 100000);
- desc.prim.b.y = av_make_q(s->display_primaries[2][1], 100000);
- prim = av_csp_primaries_id_from_desc(&desc);
- if (prim != AVCOL_PRI_UNSPECIFIED)
- avctx->color_primaries = f->color_primaries = prim;
- else
- av_log(avctx, AV_LOG_WARNING, "unknown cHRM primaries\n");
- }
-
- /* these chunks override gAMA */
- if (s->iccp_data || s->have_srgb || s->have_cicp)
- av_dict_set(&s->frame_metadata, "gamma", NULL, 0);
-
- avctx->colorspace = f->colorspace = AVCOL_SPC_RGB;
-
if (s->stereo_mode >= 0) {
AVStereo3D *stereo3d = av_stereo3d_create_side_data(f);
if (!stereo3d) {
diff --git a/tests/ref/fate/png-icc b/tests/ref/fate/png-icc
index 14de544639..1f4eab1fb0 100644
--- a/tests/ref/fate/png-icc
+++ b/tests/ref/fate/png-icc
@@ -1,5 +1,5 @@
-a50d37a0e72bddea2fcbba6fb773e2a0 *tests/data/fate/png-icc.image2
-49397 tests/data/fate/png-icc.image2
+c460cd06a88ace94d7c76a6309aa8fb8 *tests/data/fate/png-icc.image2
+49441 tests/data/fate/png-icc.image2
#tb 0: 1/25
#media_type 0: video
#codec_id 0: rawvideo
@@ -21,7 +21,7 @@ pkt_duration_time=0.040000
duration=1
duration_time=0.040000
pkt_pos=0
-pkt_size=49397
+pkt_size=49441
width=128
height=128
pix_fmt=rgb24
@@ -34,7 +34,7 @@ top_field_first=0
repeat_pict=0
color_range=pc
color_space=gbr
-color_primaries=unknown
+color_primaries=bt709
color_transfer=unknown
chroma_location=unspecified
[SIDE_DATA]
diff --git a/tests/ref/fate/png-side-data b/tests/ref/fate/png-side-data
index a4c16eb395..8f955f76bc 100644
--- a/tests/ref/fate/png-side-data
+++ b/tests/ref/fate/png-side-data
@@ -26,7 +26,7 @@ top_field_first=0
repeat_pict=0
color_range=pc
color_space=gbr
-color_primaries=unknown
+color_primaries=bt709
color_transfer=unknown
chroma_location=unspecified
[SIDE_DATA]
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