libtwolame MP2 encoding support

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

1 files changed, 226 insertions, 0 deletions

diff --git a/libavcodec/libtwolame.c b/libavcodec/libtwolame.c
new file mode 100644
index 0000000000..d8d73b3bcc
--- /dev/null
+++ b/libavcodec/libtwolame.c
@@ -0,0 +1,226 @@
+/*
+ * Interface to libtwolame for mp2 encoding
+ * Copyright (c) 2012 Paul B Mahol
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * Interface to libtwolame for mp2 encoding.
+ */
+
+#include <twolame.h>
+
+#include "libavutil/common.h"
+#include "libavutil/opt.h"
+
+#include "avcodec.h"
+#include "internal.h"
+#include "mpegaudio.h"
+
+typedef struct TWOLAMEContext {
+    AVClass *class;
+    int mode;
+    int psymodel;
+    int energy;
+    int error_protection;
+    int copyright;
+    int original;
+    int verbosity;
+
+    twolame_options *glopts;
+    int64_t next_pts;
+} TWOLAMEContext;
+
+static av_cold int twolame_encode_close(AVCodecContext *avctx)
+{
+    TWOLAMEContext *s = avctx->priv_data;
+    twolame_close(&s->glopts);
+    return 0;
+}
+
+static av_cold int twolame_encode_init(AVCodecContext *avctx)
+{
+    TWOLAMEContext *s = avctx->priv_data;
+    int ret;
+
+    avctx->frame_size = TWOLAME_SAMPLES_PER_FRAME;
+    avctx->delay      = 512 - 32 + 1;
+
+    s->glopts = twolame_init();
+    if (!s->glopts)
+        return AVERROR(ENOMEM);
+
+    twolame_set_verbosity(s->glopts, s->verbosity);
+    twolame_set_mode(s->glopts, s->mode);
+    twolame_set_psymodel(s->glopts, s->psymodel);
+    twolame_set_energy_levels(s->glopts, s->energy);
+    twolame_set_error_protection(s->glopts, s->error_protection);
+    twolame_set_copyright(s->glopts, s->copyright);
+    twolame_set_original(s->glopts, s->original);
+
+    twolame_set_num_channels(s->glopts, avctx->channels);
+    twolame_set_in_samplerate(s->glopts, avctx->sample_rate);
+    twolame_set_out_samplerate(s->glopts, avctx->sample_rate);
+    if (avctx->flags & CODEC_FLAG_QSCALE || !avctx->bit_rate) {
+        twolame_set_VBR(s->glopts, TRUE);
+        twolame_set_VBR_level(s->glopts,
+                              avctx->global_quality / (float) FF_QP2LAMBDA);
+        av_log(avctx, AV_LOG_WARNING,
+               "VBR in MP2 is a hack, use another codec that supports it.\n");
+    } else {
+        twolame_set_bitrate(s->glopts, avctx->bit_rate / 1000);
+    }
+
+    ret = twolame_init_params(s->glopts);
+    if (ret) {
+        twolame_encode_close(avctx);
+        return AVERROR_UNKNOWN;
+    }
+
+    return 0;
+}
+
+static int twolame_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
+                                const AVFrame *frame, int *got_packet_ptr)
+{
+    TWOLAMEContext *s = avctx->priv_data;
+    int ret;
+
+    if ((ret = ff_alloc_packet(avpkt, MPA_MAX_CODED_FRAME_SIZE)) < 0)
+        return ret;
+
+    if (frame) {
+        switch (avctx->sample_fmt) {
+        case AV_SAMPLE_FMT_FLT:
+            ret = twolame_encode_buffer_float32_interleaved(s->glopts,
+                                                            (const float *)frame->data[0],
+                                                            frame->nb_samples,
+                                                            avpkt->data,
+                                                            avpkt->size);
+            break;
+        case AV_SAMPLE_FMT_FLTP:
+            ret = twolame_encode_buffer_float32(s->glopts,
+                                                (const float *)frame->data[0],
+                                                (const float *)frame->data[1],
+                                                frame->nb_samples,
+                                                avpkt->data, avpkt->size);
+            break;
+        case AV_SAMPLE_FMT_S16:
+            ret = twolame_encode_buffer_interleaved(s->glopts,
+                                                    (const short int *)frame->data[0],
+                                                    frame->nb_samples,
+                                                    avpkt->data, avpkt->size);
+            break;
+        case AV_SAMPLE_FMT_S16P:
+            ret = twolame_encode_buffer(s->glopts,
+                                        (const short int *)frame->data[0],
+                                        (const short int *)frame->data[1],
+                                        frame->nb_samples,
+                                        avpkt->data, avpkt->size);
+            break;
+        default:
+            av_log(avctx, AV_LOG_ERROR,
+                   "Unsupported sample format %d.\n", avctx->sample_fmt);
+            return AVERROR_BUG;
+        }
+    } else {
+        ret = twolame_encode_flush(s->glopts, avpkt->data, avpkt->size);
+    }
+
+    if (!ret)     // no bytes written
+        return 0;
+    if (ret < 0)  // twolame error
+        return AVERROR_UNKNOWN;
+
+    avpkt->duration = ff_samples_to_time_base(avctx, frame->nb_samples);
+    if (frame) {
+        if (frame->pts != AV_NOPTS_VALUE)
+            avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->delay);
+    } else {
+        avpkt->pts = s->next_pts;
+    }
+    // this is for setting pts for flushed packet(s).
+    if (avpkt->pts != AV_NOPTS_VALUE)
+        s->next_pts = avpkt->pts + avpkt->duration;
+
+    av_shrink_packet(avpkt, ret);
+    *got_packet_ptr = 1;
+    return 0;
+}
+
+#define OFFSET(x) offsetof(TWOLAMEContext, x)
+#define AE AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
+static const AVOption options[] = {
+    { "mode", "Mpeg Mode", OFFSET(mode), AV_OPT_TYPE_INT, { .i64 = TWOLAME_AUTO_MODE }, TWOLAME_AUTO_MODE, TWOLAME_MONO, AE, "mode"},
+        { "auto", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_AUTO_MODE }, 0, 0, AE, "mode" },
+        { "stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_STEREO }, 0, 0, AE, "mode" },
+        { "joint_stereo", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_JOINT_STEREO }, 0, 0, AE, "mode" },
+        { "dual_channel", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_DUAL_CHANNEL }, 0, 0, AE, "mode" },
+        { "mono", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = TWOLAME_MONO }, 0, 0, AE, "mode" },
+    { "psymodel", "Psychoacoustic Model", OFFSET(psymodel), AV_OPT_TYPE_INT, { .i64 = 3 }, -1, 4, AE},
+    { "energy_levels","enable energy levels", OFFSET(energy), AV_OPT_TYPE_INT, { .i64 = 0 },  0, 1, AE},
+    { "error_protection","enable CRC error protection", OFFSET(error_protection), AV_OPT_TYPE_INT, { .i64 = 0 },  0, 1, AE},
+    { "copyright", "set MPEG Audio Copyright flag", OFFSET(copyright), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
+    { "original", "set MPEG Audio Original flag", OFFSET(original), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AE},
+    { "verbosity", "set library optput level (0-10)", OFFSET(verbosity), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 10, AE},
+    { NULL },
+};
+
+static const AVClass twolame_class = {
+    .class_name = "libtwolame encoder",
+    .item_name  = av_default_item_name,
+    .option     = options,
+    .version    = LIBAVUTIL_VERSION_INT,
+};
+
+static const AVCodecDefault twolame_defaults[] = {
+    { "b", "384000" },
+    { "ar", "48000" },
+    { NULL },
+};
+
+static const int twolame_samplerates[] = {
+    16000, 22050, 24000, 32000, 44100, 48000, 0
+};
+
+AVCodec ff_libtwolame_encoder = {
+    .name           = "libtwolame",
+    .long_name      = NULL_IF_CONFIG_SMALL("libtwolame MP2 (MPEG audio layer 2)"),
+    .type           = AVMEDIA_TYPE_AUDIO,
+    .id             = AV_CODEC_ID_MP2,
+    .priv_data_size = sizeof(TWOLAMEContext),
+    .init           = twolame_encode_init,
+    .encode2        = twolame_encode_frame,
+    .close          = twolame_encode_close,
+    .capabilities   = CODEC_CAP_DELAY,
+    .defaults       = twolame_defaults,
+    .priv_class     = &twolame_class,
+    .sample_fmts    = (const enum AVSampleFormat[]) {
+        AV_SAMPLE_FMT_FLT,
+        AV_SAMPLE_FMT_FLTP,
+        AV_SAMPLE_FMT_S16,
+        AV_SAMPLE_FMT_S16P,
+        AV_SAMPLE_FMT_NONE
+    },
+    .channel_layouts = (const uint64_t[]) {
+        AV_CH_LAYOUT_MONO,
+        AV_CH_LAYOUT_STEREO,
+        0 },
+    .supported_samplerates = twolame_samplerates,
+};