diff ffmpeg/libavformat/adtsenc.c @ 11:f445c3017523

new files

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ffmpeg/libavformat/adtsenc.c	Sun Apr 21 11:16:23 2013 +0200
@@ -0,0 +1,175 @@
+/*
+ * ADTS muxer.
+ * Copyright (c) 2006 Baptiste Coudurier <[e-mail]>
+ *                    Mans Rullgard <[e-mail]>
+ *
+ * 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 "libavcodec/get_bits.h"
+#include "libavcodec/put_bits.h"
+#include "libavcodec/avcodec.h"
+#include "libavcodec/mpeg4audio.h"
+#include "avformat.h"
+
+#define ADTS_HEADER_SIZE 7
+
+typedef struct {
+    int write_adts;
+    int objecttype;
+    int sample_rate_index;
+    int channel_conf;
+    int pce_size;
+    uint8_t pce_data[MAX_PCE_SIZE];
+} ADTSContext;
+
+#define ADTS_MAX_FRAME_BYTES ((1 << 13) - 1)
+
+static int adts_decode_extradata(AVFormatContext *s, ADTSContext *adts, uint8_t *buf, int size)
+{
+    GetBitContext gb;
+    PutBitContext pb;
+    MPEG4AudioConfig m4ac;
+    int off;
+
+    init_get_bits(&gb, buf, size * 8);
+    off = avpriv_mpeg4audio_get_config(&m4ac, buf, size * 8, 1);
+    if (off < 0)
+        return off;
+    skip_bits_long(&gb, off);
+    adts->objecttype        = m4ac.object_type - 1;
+    adts->sample_rate_index = m4ac.sampling_index;
+    adts->channel_conf      = m4ac.chan_config;
+
+    if (adts->objecttype > 3U) {
+        av_log(s, AV_LOG_ERROR, "MPEG-4 AOT %d is not allowed in ADTS\n", adts->objecttype+1);
+        return -1;
+    }
+    if (adts->sample_rate_index == 15) {
+        av_log(s, AV_LOG_ERROR, "Escape sample rate index illegal in ADTS\n");
+        return -1;
+    }
+    if (get_bits(&gb, 1)) {
+        av_log(s, AV_LOG_ERROR, "960/120 MDCT window is not allowed in ADTS\n");
+        return -1;
+    }
+    if (get_bits(&gb, 1)) {
+        av_log(s, AV_LOG_ERROR, "Scalable configurations are not allowed in ADTS\n");
+        return -1;
+    }
+    if (get_bits(&gb, 1)) {
+        av_log(s, AV_LOG_ERROR, "Extension flag is not allowed in ADTS\n");
+        return -1;
+    }
+    if (!adts->channel_conf) {
+        init_put_bits(&pb, adts->pce_data, MAX_PCE_SIZE);
+
+        put_bits(&pb, 3, 5); //ID_PCE
+        adts->pce_size = (avpriv_copy_pce_data(&pb, &gb) + 3) / 8;
+        flush_put_bits(&pb);
+    }
+
+    adts->write_adts = 1;
+
+    return 0;
+}
+
+static int adts_write_header(AVFormatContext *s)
+{
+    ADTSContext *adts = s->priv_data;
+    AVCodecContext *avc = s->streams[0]->codec;
+
+    if (avc->extradata_size > 0 &&
+            adts_decode_extradata(s, adts, avc->extradata, avc->extradata_size) < 0)
+        return -1;
+
+    return 0;
+}
+
+static int adts_write_frame_header(ADTSContext *ctx,
+                                   uint8_t *buf, int size, int pce_size)
+{
+    PutBitContext pb;
+
+    unsigned full_frame_size = (unsigned)ADTS_HEADER_SIZE + size + pce_size;
+    if (full_frame_size > ADTS_MAX_FRAME_BYTES) {
+        av_log(NULL, AV_LOG_ERROR, "ADTS frame size too large: %u (max %d)\n",
+               full_frame_size, ADTS_MAX_FRAME_BYTES);
+        return AVERROR_INVALIDDATA;
+    }
+
+    init_put_bits(&pb, buf, ADTS_HEADER_SIZE);
+
+    /* adts_fixed_header */
+    put_bits(&pb, 12, 0xfff);   /* syncword */
+    put_bits(&pb, 1, 0);        /* ID */
+    put_bits(&pb, 2, 0);        /* layer */
+    put_bits(&pb, 1, 1);        /* protection_absent */
+    put_bits(&pb, 2, ctx->objecttype); /* profile_objecttype */
+    put_bits(&pb, 4, ctx->sample_rate_index);
+    put_bits(&pb, 1, 0);        /* private_bit */
+    put_bits(&pb, 3, ctx->channel_conf); /* channel_configuration */
+    put_bits(&pb, 1, 0);        /* original_copy */
+    put_bits(&pb, 1, 0);        /* home */
+
+    /* adts_variable_header */
+    put_bits(&pb, 1, 0);        /* copyright_identification_bit */
+    put_bits(&pb, 1, 0);        /* copyright_identification_start */
+    put_bits(&pb, 13, full_frame_size); /* aac_frame_length */
+    put_bits(&pb, 11, 0x7ff);   /* adts_buffer_fullness */
+    put_bits(&pb, 2, 0);        /* number_of_raw_data_blocks_in_frame */
+
+    flush_put_bits(&pb);
+
+    return 0;
+}
+
+static int adts_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    ADTSContext *adts = s->priv_data;
+    AVIOContext *pb = s->pb;
+    uint8_t buf[ADTS_HEADER_SIZE];
+
+    if (!pkt->size)
+        return 0;
+    if (adts->write_adts) {
+        int err = adts_write_frame_header(adts, buf, pkt->size,
+                                             adts->pce_size);
+        if (err < 0)
+            return err;
+        avio_write(pb, buf, ADTS_HEADER_SIZE);
+        if (adts->pce_size) {
+            avio_write(pb, adts->pce_data, adts->pce_size);
+            adts->pce_size = 0;
+        }
+    }
+    avio_write(pb, pkt->data, pkt->size);
+
+    return 0;
+}
+
+AVOutputFormat ff_adts_muxer = {
+    .name              = "adts",
+    .long_name         = NULL_IF_CONFIG_SMALL("ADTS AAC (Advanced Audio Coding)"),
+    .mime_type         = "audio/aac",
+    .extensions        = "aac,adts",
+    .priv_data_size    = sizeof(ADTSContext),
+    .audio_codec       = AV_CODEC_ID_AAC,
+    .video_codec       = AV_CODEC_ID_NONE,
+    .write_header      = adts_write_header,
+    .write_packet      = adts_write_packet,
+};