avcodec: estimate output bitrate for uncompressed video codecs

Allows to get a more realistic total bitrate (and estimated file size)
in avi_write_header. Previously a static default value of 200k was
assumed.

Adds an internal helper function for bitrate guessing.

Signed-off-by: Tobias Rapp <t.rapp@noa-archive.com>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>

9 files changed, 56 insertions, 0 deletions

diff --git a/libavcodec/internal.h b/libavcodec/internal.h
index 6e93eeb..e5f132a 100644
--- a/libavcodec/internal.h
+++ b/libavcodec/internal.h
@@ -363,4 +363,10 @@ int ff_side_data_set_encoder_stats(AVPacket *pkt, int quality, int64_t *error, i
 int ff_alloc_a53_sei(const AVFrame *frame, size_t prefix_len,
                      void **data, size_t *sei_size);
 
+/**
+ * Get an estimated video bitrate based on frame size, frame rate and coded
+ * bits per pixel.
+ */
+int64_t ff_guess_coded_bitrate(AVCodecContext *avctx);
+
 #endif /* AVCODEC_INTERNAL_H */
diff --git a/libavcodec/r210enc.c b/libavcodec/r210enc.c
index 65b3c06..a55e543 100644
--- a/libavcodec/r210enc.c
+++ b/libavcodec/r210enc.c
@@ -24,6 +24,18 @@
 #include "internal.h"
 #include "bytestream.h"
 
+static av_cold int encode_init(AVCodecContext *avctx)
+{
+    int aligned_width = FFALIGN(avctx->width,
+                                avctx->codec_id == AV_CODEC_ID_R10K ? 1 : 64);
+
+    avctx->bits_per_coded_sample = 32;
+    if (avctx->width > 0)
+        avctx->bit_rate = ff_guess_coded_bitrate(avctx) * aligned_width / avctx->width;
+
+    return 0;
+}
+
 static int encode_frame(AVCodecContext *avctx, AVPacket *pkt,
                         const AVFrame *pic, int *got_packet)
 {
@@ -73,6 +85,7 @@ AVCodec ff_r210_encoder = {
     .long_name      = NULL_IF_CONFIG_SMALL("Uncompressed RGB 10-bit"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_R210,
+    .init           = encode_init,
     .encode2        = encode_frame,
     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB48, AV_PIX_FMT_NONE },
     .capabilities   = AV_CODEC_CAP_INTRA_ONLY,
@@ -84,6 +97,7 @@ AVCodec ff_r10k_encoder = {
     .long_name      = NULL_IF_CONFIG_SMALL("AJA Kona 10-bit RGB Codec"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_R10K,
+    .init           = encode_init,
     .encode2        = encode_frame,
     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB48, AV_PIX_FMT_NONE },
     .capabilities   = AV_CODEC_CAP_INTRA_ONLY,
@@ -95,6 +109,7 @@ AVCodec ff_avrp_encoder = {
     .long_name      = NULL_IF_CONFIG_SMALL("Avid 1:1 10-bit RGB Packer"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_AVRP,
+    .init           = encode_init,
     .encode2        = encode_frame,
     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_RGB48, AV_PIX_FMT_NONE },
     .capabilities   = AV_CODEC_CAP_INTRA_ONLY,
diff --git a/libavcodec/rawenc.c b/libavcodec/rawenc.c
index a2d5ccc..d181b74 100644
--- a/libavcodec/rawenc.c
+++ b/libavcodec/rawenc.c
@@ -44,6 +44,8 @@ FF_ENABLE_DEPRECATION_WARNINGS
     avctx->bits_per_coded_sample = av_get_bits_per_pixel(desc);
     if(!avctx->codec_tag)
         avctx->codec_tag = avcodec_pix_fmt_to_codec_tag(avctx->pix_fmt);
+    avctx->bit_rate = ff_guess_coded_bitrate(avctx);
+
     return 0;
 }
 
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 6f7b2e7..63a6349 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -4343,3 +4343,24 @@ int ff_alloc_a53_sei(const AVFrame *frame, size_t prefix_len,
 
     return 0;
 }
+
+int64_t ff_guess_coded_bitrate(AVCodecContext *avctx)
+{
+    AVRational framerate = avctx->framerate;
+    int bits_per_coded_sample = avctx->bits_per_coded_sample;
+    int64_t bitrate;
+
+    if (!(framerate.num && framerate.den))
+        framerate = av_inv_q(avctx->time_base);
+    if (!(framerate.num && framerate.den))
+        return 0;
+
+    if (!bits_per_coded_sample) {
+        const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(avctx->pix_fmt);
+        bits_per_coded_sample = av_get_bits_per_pixel(desc);
+    }
+    bitrate = (int64_t)bits_per_coded_sample * avctx->width * avctx->height *
+              framerate.num / framerate.den;
+
+    return bitrate;
+}
diff --git a/libavcodec/v210enc.c b/libavcodec/v210enc.c
index d3a8e26..a6afbbf 100644
--- a/libavcodec/v210enc.c
+++ b/libavcodec/v210enc.c
@@ -110,6 +110,9 @@ FF_ENABLE_DEPRECATION_WARNINGS
 
     ff_v210enc_init(s);
 
+    avctx->bits_per_coded_sample = 20;
+    avctx->bit_rate = ff_guess_coded_bitrate(avctx) * 16 / 15;
+
     return 0;
 }
 
diff --git a/libavcodec/v308enc.c b/libavcodec/v308enc.c
index b60a72c..e88f1f4 100644
--- a/libavcodec/v308enc.c
+++ b/libavcodec/v308enc.c
@@ -31,6 +31,9 @@ static av_cold int v308_encode_init(AVCodecContext *avctx)
         return AVERROR_INVALIDDATA;
     }
 
+    avctx->bits_per_coded_sample = 24;
+    avctx->bit_rate = ff_guess_coded_bitrate(avctx);
+
     return 0;
 }
 
diff --git a/libavcodec/v408enc.c b/libavcodec/v408enc.c
index f37f360..e12965b 100644
--- a/libavcodec/v408enc.c
+++ b/libavcodec/v408enc.c
@@ -26,6 +26,8 @@
 
 static av_cold int v408_encode_init(AVCodecContext *avctx)
 {
+    avctx->bits_per_coded_sample = 32;
+    avctx->bit_rate = ff_guess_coded_bitrate(avctx);
 
     return 0;
 }
diff --git a/libavcodec/v410enc.c b/libavcodec/v410enc.c
index f35ff75..5e24502 100644
--- a/libavcodec/v410enc.c
+++ b/libavcodec/v410enc.c
@@ -32,6 +32,9 @@ static av_cold int v410_encode_init(AVCodecContext *avctx)
         return AVERROR_INVALIDDATA;
     }
 
+    avctx->bits_per_coded_sample = 32;
+    avctx->bit_rate = ff_guess_coded_bitrate(avctx);
+
     return 0;
 }
 
diff --git a/libavcodec/y41penc.c b/libavcodec/y41penc.c
index 94acc34..ca94a3c 100644
--- a/libavcodec/y41penc.c
+++ b/libavcodec/y41penc.c
@@ -31,6 +31,7 @@ static av_cold int y41p_encode_init(AVCodecContext *avctx)
     }
 
     avctx->bits_per_coded_sample = 12;
+    avctx->bit_rate = ff_guess_coded_bitrate(avctx);
 
     return 0;
 }