[FFmpeg-devel] [PATCH 2/2] avcodec: add pcm-bluray encoder

Paul B Mahol onemda at gmail.com
Sat Feb 26 21:31:43 EET 2022


Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
 libavcodec/Makefile        |   1 +
 libavcodec/allcodecs.c     |   1 +
 libavcodec/pcm-blurayenc.c | 291 +++++++++++++++++++++++++++++++++++++
 3 files changed, 293 insertions(+)
 create mode 100644 libavcodec/pcm-blurayenc.c

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 6076b4ad80..e34a9ae862 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -800,6 +800,7 @@ OBJS-$(CONFIG_ZMBV_ENCODER)            += zmbvenc.o
 # (AD)PCM decoders/encoders
 OBJS-$(CONFIG_PCM_ALAW_DECODER)           += pcm.o
 OBJS-$(CONFIG_PCM_ALAW_ENCODER)           += pcm.o
+OBJS-$(CONFIG_PCM_BLURAY_ENCODER)         += pcm-blurayenc.o
 OBJS-$(CONFIG_PCM_BLURAY_DECODER)         += pcm-bluray.o
 OBJS-$(CONFIG_PCM_DVD_DECODER)            += pcm-dvd.o
 OBJS-$(CONFIG_PCM_DVD_ENCODER)            += pcm-dvdenc.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index d1e10197de..1be67e3ec3 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -531,6 +531,7 @@ extern const AVCodec ff_xma2_decoder;
 /* PCM codecs */
 extern const AVCodec ff_pcm_alaw_encoder;
 extern const AVCodec ff_pcm_alaw_decoder;
+extern const AVCodec ff_pcm_bluray_encoder;
 extern const AVCodec ff_pcm_bluray_decoder;
 extern const AVCodec ff_pcm_dvd_encoder;
 extern const AVCodec ff_pcm_dvd_decoder;
diff --git a/libavcodec/pcm-blurayenc.c b/libavcodec/pcm-blurayenc.c
new file mode 100644
index 0000000000..9201ad9690
--- /dev/null
+++ b/libavcodec/pcm-blurayenc.c
@@ -0,0 +1,291 @@
+/*
+ * LPCM codecs for PCM formats found in Blu-ray m2ts streams
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/channel_layout.h"
+#include "avcodec.h"
+#include "bytestream.h"
+#include "encode.h"
+#include "internal.h"
+
+typedef struct BlurayPCMEncContext {
+    uint16_t header;      // Header added to every frame
+} BlurayPCMEncContext;
+
+static av_cold int pcm_bluray_encode_init(AVCodecContext *avctx)
+{
+    BlurayPCMEncContext *s = avctx->priv_data;
+    uint8_t ch_layout;
+    int quant, freq;
+
+    switch (avctx->sample_rate) {
+    case 48000:
+        freq = 1;
+        break;
+    case 96000:
+        freq = 4;
+        break;
+    case 192000:
+        freq = 5;
+        break;
+    }
+
+    switch (avctx->sample_fmt) {
+    case AV_SAMPLE_FMT_S16:
+        avctx->bits_per_coded_sample = 16;
+        quant = 1;
+        break;
+    case AV_SAMPLE_FMT_S32:
+        avctx->bits_per_coded_sample = 24;
+        quant = 3;
+        break;
+    }
+
+    switch (avctx->channel_layout) {
+    case AV_CH_LAYOUT_MONO:
+        ch_layout = 1;
+        break;
+    case AV_CH_LAYOUT_STEREO:
+        ch_layout = 3;
+        break;
+    case AV_CH_LAYOUT_SURROUND:
+        ch_layout = 4;
+        break;
+    case AV_CH_LAYOUT_2_1:
+        ch_layout = 5;
+        break;
+    case AV_CH_LAYOUT_4POINT0:
+        ch_layout = 6;
+        break;
+    case AV_CH_LAYOUT_2_2:
+        ch_layout = 7;
+        break;
+    case AV_CH_LAYOUT_5POINT0:
+        ch_layout = 8;
+        break;
+    case AV_CH_LAYOUT_5POINT1:
+        ch_layout = 9;
+        break;
+    case AV_CH_LAYOUT_7POINT0:
+        ch_layout = 10;
+        break;
+    case AV_CH_LAYOUT_7POINT1:
+        ch_layout = 11;
+        break;
+    default:
+        return AVERROR_BUG;
+    }
+
+    s->header = (((ch_layout << 4) | freq) << 8) | (quant << 6);
+
+    return 0;
+}
+
+static int pcm_bluray_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
+                                   const AVFrame *frame, int *got_packet_ptr)
+{
+    BlurayPCMEncContext *s = avctx->priv_data;
+    int sample_size, samples, channel, num_dest_channels;
+    const int16_t *src16;
+    const int32_t *src32;
+    unsigned pkt_size;
+    PutByteContext pb;
+    int ret;
+
+    num_dest_channels = FFALIGN(avctx->channels, 2);
+    sample_size = (num_dest_channels *
+                   (avctx->sample_fmt == AV_SAMPLE_FMT_S16 ? 16 : 24)) >> 3;
+    samples = frame->nb_samples;
+
+    pkt_size = sample_size * samples + 4;
+
+    if ((ret = ff_get_encode_buffer(avctx, avpkt, pkt_size, 0)) < 0)
+        return ret;
+
+    AV_WB16(avpkt->data, pkt_size - 4);
+    AV_WB16(avpkt->data + 2, s->header);
+
+    src16 = (const int16_t *)frame->data[0];
+    src32 = (const int32_t *)frame->data[0];
+
+    bytestream2_init_writer(&pb, avpkt->data + 4, avpkt->size - 4);
+
+    switch (avctx->channel_layout) {
+    /* cases with same number of source and coded channels */
+    case AV_CH_LAYOUT_STEREO:
+    case AV_CH_LAYOUT_4POINT0:
+    case AV_CH_LAYOUT_2_2:
+        samples *= num_dest_channels;
+        if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
+#if HAVE_BIGENDIAN
+            bytestream2_put_buffer(&pb, src16, buf_size);
+#else
+            do {
+                bytestream2_put_be16u(&pb, *src16++);
+            } while (--samples);
+#endif
+        } else {
+            do {
+                bytestream2_put_be24u(&pb, (*src32++) >> 8);
+            } while (--samples);
+        }
+        break;
+    /* cases where number of source channels = coded channels + 1 */
+    case AV_CH_LAYOUT_MONO:
+    case AV_CH_LAYOUT_SURROUND:
+    case AV_CH_LAYOUT_2_1:
+    case AV_CH_LAYOUT_5POINT0:
+        if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
+            do {
+#if HAVE_BIGENDIAN
+                bytestream2_put_bufferu(&pb, src16, avctx->channels * 2);
+                src16 += avctx->channels;
+#else
+                channel = avctx->channels;
+                do {
+                    bytestream2_put_be16u(&pb, *src16++);
+                } while (--channel);
+#endif
+                bytestream2_put_ne16(&pb, 0);
+            } while (--samples);
+        } else {
+            do {
+                channel = avctx->channels;
+                do {
+                    bytestream2_put_be24u(&pb, (*src32++) >> 8);
+                } while (--channel);
+                bytestream2_put_ne24(&pb, 0);
+            } while (--samples);
+        }
+        break;
+        /* remapping: L, R, C, LBack, RBack, LF */
+    case AV_CH_LAYOUT_5POINT1:
+        if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
+            do {
+                bytestream2_put_be16u(&pb, src16[0]);
+                bytestream2_put_be16u(&pb, src16[1]);
+                bytestream2_put_be16u(&pb, src16[2]);
+                bytestream2_put_be16u(&pb, src16[4]);
+                bytestream2_put_be16u(&pb, src16[5]);
+                bytestream2_put_be16u(&pb, src16[3]);
+                src16 += 6;
+            } while (--samples);
+        } else {
+            do {
+                bytestream2_put_be24u(&pb, src32[0] >> 8);
+                bytestream2_put_be24u(&pb, src32[1] >> 8);
+                bytestream2_put_be24u(&pb, src32[2] >> 8);
+                bytestream2_put_be24u(&pb, src32[4] >> 8);
+                bytestream2_put_be24u(&pb, src32[5] >> 8);
+                bytestream2_put_be24u(&pb, src32[3] >> 8);
+                src32 += 6;
+            } while (--samples);
+        }
+        break;
+        /* remapping: L, R, C, LSide, LBack, RBack, RSide, <unused> */
+    case AV_CH_LAYOUT_7POINT0:
+        if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
+            do {
+                bytestream2_put_be16u(&pb, src16[0]);
+                bytestream2_put_be16u(&pb, src16[1]);
+                bytestream2_put_be16u(&pb, src16[2]);
+                bytestream2_put_be16u(&pb, src16[5]);
+                bytestream2_put_be16u(&pb, src16[3]);
+                bytestream2_put_be16u(&pb, src16[4]);
+                bytestream2_put_be16u(&pb, src16[6]);
+                src16 += 7;
+                bytestream2_put_ne16(&pb, 0);
+            } while (--samples);
+        } else {
+            do {
+                bytestream2_put_be24u(&pb, src32[0] >> 8);
+                bytestream2_put_be24u(&pb, src32[1] >> 8);
+                bytestream2_put_be24u(&pb, src32[2] >> 8);
+                bytestream2_put_be24u(&pb, src32[5] >> 8);
+                bytestream2_put_be24u(&pb, src32[3] >> 8);
+                bytestream2_put_be24u(&pb, src32[4] >> 8);
+                bytestream2_put_be24u(&pb, src32[6] >> 8);
+                src32 += 7;
+                bytestream2_put_ne24(&pb, 0);
+            } while (--samples);
+        }
+        break;
+        /* remapping: L, R, C, LSide, LBack, RBack, RSide, LF */
+    case AV_CH_LAYOUT_7POINT1:
+        if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
+            do {
+                bytestream2_put_be16u(&pb, src16[0]);
+                bytestream2_put_be16u(&pb, src16[1]);
+                bytestream2_put_be16u(&pb, src16[2]);
+                bytestream2_put_be16u(&pb, src16[6]);
+                bytestream2_put_be16u(&pb, src16[4]);
+                bytestream2_put_be16u(&pb, src16[5]);
+                bytestream2_put_be16u(&pb, src16[7]);
+                bytestream2_put_be16u(&pb, src16[3]);
+                src16 += 8;
+            } while (--samples);
+        } else {
+            do {
+                bytestream2_put_be24u(&pb, src32[0]);
+                bytestream2_put_be24u(&pb, src32[1]);
+                bytestream2_put_be24u(&pb, src32[2]);
+                bytestream2_put_be24u(&pb, src32[6]);
+                bytestream2_put_be24u(&pb, src32[4]);
+                bytestream2_put_be24u(&pb, src32[5]);
+                bytestream2_put_be24u(&pb, src32[7]);
+                bytestream2_put_be24u(&pb, src32[3]);
+                src32 += 8;
+            } while (--samples);
+        }
+        break;
+    }
+
+    avpkt->pts = frame->pts;
+    avpkt->duration = ff_samples_to_time_base(avctx, frame->nb_samples);
+    *got_packet_ptr = 1;
+
+    return 0;
+}
+
+const AVCodec ff_pcm_bluray_encoder = {
+    .name                  = "pcm_bluray",
+    .long_name             = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for Blu-ray media"),
+    .type                  = AVMEDIA_TYPE_AUDIO,
+    .id                    = AV_CODEC_ID_PCM_BLURAY,
+    .priv_data_size        = sizeof(BlurayPCMEncContext),
+    .init                  = pcm_bluray_encode_init,
+    .encode2               = pcm_bluray_encode_frame,
+    .capabilities          = AV_CODEC_CAP_SMALL_LAST_FRAME,
+    .supported_samplerates = (const int[]) { 48000, 96000, 192000, 0 },
+    .channel_layouts = (const uint64_t[]) {
+        AV_CH_LAYOUT_MONO,
+        AV_CH_LAYOUT_STEREO,
+        AV_CH_LAYOUT_SURROUND,
+        AV_CH_LAYOUT_2_1,
+        AV_CH_LAYOUT_4POINT0,
+        AV_CH_LAYOUT_2_2,
+        AV_CH_LAYOUT_5POINT0,
+        AV_CH_LAYOUT_5POINT1,
+        AV_CH_LAYOUT_7POINT0,
+        AV_CH_LAYOUT_7POINT1,
+        0 },
+    .sample_fmts           = (const enum AVSampleFormat[]) {
+        AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_NONE },
+    .caps_internal         = FF_CODEC_CAP_INIT_THREADSAFE,
+};
-- 
2.33.0



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