[FFmpeg-devel] [PATCH 06/10] avcodec/dovi_rpu: add ff_dovi_configure()

Niklas Haas ffmpeg at haasn.xyz
Wed Apr 3 18:43:26 EEST 2024


From: Niklas Haas <git at haasn.dev>

We need to set up the configuration struct appropriately based on the
codec type, colorspace metadata, and presence/absence of an EL (though,
we currently don't support an EL).

When present, we use the signalled RPU data header to help infer (and
validate) the right values.
---
 libavcodec/dovi_rpu.c | 176 ++++++++++++++++++++++++++++++++++++++++++
 libavcodec/dovi_rpu.h |  14 +++-
 2 files changed, 189 insertions(+), 1 deletion(-)

diff --git a/libavcodec/dovi_rpu.c b/libavcodec/dovi_rpu.c
index 4da711d763e..b4e8d0cdea4 100644
--- a/libavcodec/dovi_rpu.c
+++ b/libavcodec/dovi_rpu.c
@@ -144,6 +144,182 @@ static int guess_hevc_profile(const AVDOVIRpuDataHeader *hdr)
     return 0; /* unknown */
 }
 
+static struct {
+    uint64_t pps; // maximum pixels per second
+    int width; // maximum width
+    int main; // maximum bitrate in main tier
+    int high; // maximum bitrate in high tier
+} dv_levels[] = {
+     [1] = {1280*720*24,    1280,  20,  50},
+     [2] = {1280*720*30,    1280,  20,  50},
+     [3] = {1920*1080*24,   1920,  20,  70},
+     [4] = {1920*1080*30,   2560,  20,  70},
+     [5] = {1920*1080*60,   3840,  20,  70},
+     [6] = {3840*2160*24,   3840,  25, 130},
+     [7] = {3840*2160*30,   3840,  25, 130},
+     [8] = {3840*2160*48,   3840,  40, 130},
+     [9] = {3840*2160*60,   3840,  40, 130},
+    [10] = {3840*2160*120,  3840,  60, 240},
+    [11] = {3840*2160*120,  7680,  60, 240},
+    [12] = {7680*4320*60,   7680, 120, 450},
+    [13] = {7680*4320*120u, 7680, 240, 800},
+};
+
+int ff_dovi_configure(DOVIContext *s, AVCodecContext *avctx)
+{
+    AVDOVIDecoderConfigurationRecord *cfg;
+    const AVDOVIRpuDataHeader *hdr = NULL;
+    const AVFrameSideData *sd;
+    int dv_profile, dv_level, bl_compat_id;
+    size_t cfg_size;
+    uint64_t pps;
+
+    if (!avctx->dolbyvision)
+        goto skip;
+
+    sd = av_frame_side_data_get(avctx->decoded_side_data,
+                                avctx->nb_decoded_side_data, AV_FRAME_DATA_DOVI_METADATA);
+
+    if (sd)
+        hdr = av_dovi_get_header((const AVDOVIMetadata *) sd->data);
+
+    if (avctx->dolbyvision == FF_DOLBYVISION_AUTO && !hdr)
+        goto skip;
+
+    switch (avctx->codec_id) {
+    case AV_CODEC_ID_AV1:  dv_profile = 10; break;
+    case AV_CODEC_ID_H264: dv_profile = 9;  break;
+    case AV_CODEC_ID_HEVC: dv_profile = hdr ? guess_hevc_profile(hdr) : 8; break;
+    default:
+        /* No other encoder should be calling this! */
+        av_assert0(0);
+        return AVERROR_BUG;
+    }
+
+    if (avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {
+        if (dv_profile == 9) {
+            if (avctx->pix_fmt != AV_PIX_FMT_YUV420P)
+                dv_profile = 0;
+        } else {
+            if (avctx->pix_fmt != AV_PIX_FMT_YUV420P10)
+                dv_profile = 0;
+        }
+    }
+
+    switch (dv_profile) {
+    case 0: /* None */
+        bl_compat_id = -1;
+        break;
+    case 4: /* HEVC with enhancement layer */
+    case 7:
+        if (avctx->dolbyvision > 0) {
+            av_log(s->logctx, AV_LOG_ERROR, "Coding of Dolby Vision enhancement "
+                   "layers is currently unsupported.");
+            return AVERROR_PATCHWELCOME;
+        } else {
+            goto skip;
+        }
+    case 5: /* HEVC with proprietary IPTPQc2 */
+        bl_compat_id = 0;
+        break;
+    case 10:
+        /* FIXME: check for proper H.273 tags once those are added */
+        if (hdr && hdr->bl_video_full_range_flag) {
+            /* AV1 with proprietary IPTPQc2 */
+            bl_compat_id = 0;
+            break;
+        }
+        /* fall through */
+    case 8: /* HEVC (or AV1) with BL compatibility */
+        if (avctx->colorspace == AVCOL_SPC_BT2020_NCL &&
+            avctx->color_primaries == AVCOL_PRI_BT2020 &&
+            avctx->color_trc == AVCOL_TRC_SMPTE2084) {
+            bl_compat_id = 1;
+        } else if (avctx->colorspace == AVCOL_SPC_BT2020_NCL &&
+                   avctx->color_primaries == AVCOL_PRI_BT2020 &&
+                   avctx->color_trc == AVCOL_TRC_ARIB_STD_B67) {
+            bl_compat_id = 4;
+        } else if (avctx->colorspace == AVCOL_SPC_BT709 &&
+                   avctx->color_primaries == AVCOL_PRI_BT709 &&
+                   avctx->color_trc == AVCOL_TRC_BT709) {
+            bl_compat_id = 2;
+        } else {
+            /* Not a valid colorspace combination */
+            bl_compat_id = -1;
+        }
+    }
+
+    if (!dv_profile || bl_compat_id < 0) {
+        if (avctx->dolbyvision > 0) {
+            av_log(s->logctx, AV_LOG_ERROR, "Dolby Vision enabled, but could "
+                   "not determine profile and compaatibility mode. Double-check "
+                   "colorspace and format settings for compatibility?\n");
+            return AVERROR(EINVAL);
+        }
+        goto skip;
+    }
+
+    pps = avctx->width * avctx->height;
+    if (avctx->framerate.num) {
+        pps = pps * avctx->framerate.num / avctx->framerate.den;
+    } else {
+        pps *= 25; /* sanity fallback */
+    }
+
+    dv_level = 0;
+    for (int i = 1; i < FF_ARRAY_ELEMS(dv_levels); i++) {
+        if (pps > dv_levels[i].pps)
+            continue;
+        if (avctx->width > dv_levels[i].width)
+            continue;
+        /* In theory, we should also test the bitrate when known, and
+         * distinguish between main and high tier. In practice, just ignore
+         * the bitrate constraints and hope they work out. This would ideally
+         * be handled by either the encoder or muxer directly. */
+        dv_level = i;
+        break;
+    }
+
+    if (!dv_level) {
+        if (avctx->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
+            av_log(s->logctx, AV_LOG_ERROR, "Coded PPS (%"PRIu64") and width (%d) "
+                   "exceed Dolby Vision limitations\n", pps, avctx->width);
+            return AVERROR(EINVAL);
+        } else {
+            av_log(s->logctx, AV_LOG_WARNING, "Coded PPS (%"PRIu64") and width (%d) "
+                   "exceed Dolby Vision limitations. Ignoring, resulting file "
+                   "may be non-conforming.\n", pps, avctx->width);
+            dv_level = FF_ARRAY_ELEMS(dv_levels) - 1;
+        }
+    }
+
+    cfg = av_dovi_alloc(&cfg_size);
+    if (!cfg)
+        return AVERROR(ENOMEM);
+
+    if (!av_packet_side_data_add(&avctx->coded_side_data, &avctx->nb_coded_side_data,
+                                 AV_PKT_DATA_DOVI_CONF, cfg, cfg_size, 0)) {
+        av_free(cfg);
+        return AVERROR(ENOMEM);
+    }
+
+    cfg->dv_version_major = 1;
+    cfg->dv_version_minor = 0;
+    cfg->dv_profile = dv_profile;
+    cfg->dv_level = dv_level;
+    cfg->rpu_present_flag = 1;
+    cfg->el_present_flag = 0;
+    cfg->bl_present_flag = 1;
+    cfg->dv_bl_signal_compatibility_id = bl_compat_id;
+
+    s->cfg = *cfg;
+    return 0;
+
+skip:
+    s->cfg = (AVDOVIDecoderConfigurationRecord) {0};
+    return 0;
+}
+
 static inline uint64_t get_ue_coef(GetBitContext *gb, const AVDOVIRpuDataHeader *hdr)
 {
     uint64_t ipart;
diff --git a/libavcodec/dovi_rpu.h b/libavcodec/dovi_rpu.h
index 9a68e45bf1b..33e19dd037c 100644
--- a/libavcodec/dovi_rpu.h
+++ b/libavcodec/dovi_rpu.h
@@ -26,6 +26,7 @@
 
 #include "libavutil/dovi_meta.h"
 #include "libavutil/frame.h"
+#include "avcodec.h"
 
 #define DOVI_MAX_DM_ID 15
 typedef struct DOVIContext {
@@ -33,7 +34,8 @@ typedef struct DOVIContext {
 
     /**
      * Currently active dolby vision configuration, or {0} for none.
-     * Set by the user when decoding.
+     * Set by the user when decoding. Generated by ff_dovi_configure()
+     * when encoding.
      *
      * Note: sizeof(cfg) is not part of the libavutil ABI, so users should
      * never pass &cfg to any other library calls. This is included merely as
@@ -96,4 +98,14 @@ int ff_dovi_rpu_parse(DOVIContext *s, const uint8_t *rpu, size_t rpu_size,
  */
 int ff_dovi_attach_side_data(DOVIContext *s, AVFrame *frame);
 
+/**
+ * Configure the encoder for Dolby Vision encoding. Generates a configuration
+ * record in s->cfg, and attaches it to avctx->coded_side_data. Sets the correct
+ * profile and compatibility ID based on the tagged AVCodecContext colorspace
+ * metadata, and the correct level based on the resolution and tagged framerate.
+ *
+ * Returns 0 or a negative error code.
+ */
+int ff_dovi_configure(DOVIContext *s, AVCodecContext *avctx);
+
 #endif /* AVCODEC_DOVI_RPU_H */
-- 
2.44.0



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