tests/fate: add an AU G.726LE encoding tag round-trip test

Cover 2-, 3-, 4- and 5-bit G.726LE, bit-rate fallback when
bits_per_coded_sample is unset, and rejection of unsupported bit widths.
Compare explicit widths with bitrate fallback for two-channel streams too.

Use an initialized payload and the existing memory-backed AVIO helper for
deterministic readback without custom read/seek callbacks.

Signed-off-by: Jun Zhao <barryjzhao@tencent.com>

libavformat/Makefile

@@ -804,6 +804,7 @@ TESTPROGS-$(CONFIG_NETWORK)              += noproxy
 TESTPROGS-$(CONFIG_SRTP)                 += srtp
 TESTPROGS-$(CONFIG_IMF_DEMUXER)          += imf
 TESTPROGS-$(CONFIG_MP3_MUXER)            += id3v2enc id3v2chap
+TESTPROGS-$(CONFIG_AU_MUXER)             += auenc
 TESTPROGS-$(CONFIG_OGG_MUXER)            += ogg_pages
 
 TOOLS     = aviocat                                                     \

libavformat/tests/.gitignore

@@ -1,3 +1,4 @@
+/auenc
 /id3v2
 /id3v2enc
 /fifo_muxer

libavformat/tests/auenc.c

@@ -0,0 +1,144 @@
+/*
+ * 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 <inttypes.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "libavutil/mem.h"
+#include "libavformat/avformat.h"
+#include "libavformat/avio_internal.h"
+
+#define AU_PAYLOAD 80
+
+static int run_case(int channels, int bps, int64_t bit_rate)
+{
+    AVFormatContext *out = NULL, *in = NULL;
+    AVIOContext *pb = NULL;
+    FFIOContext in_pb;
+    AVStream *st;
+    AVPacket *pkt = NULL;
+    uint8_t *buf = NULL;
+    int ret, size;
+
+    ret = avformat_alloc_output_context2(&out, NULL, "au", NULL);
+    if (ret < 0)
+        return 1;
+    if (avio_open_dyn_buf(&pb) < 0) {
+        ret = 1;
+        goto done;
+    }
+    out->pb = pb;
+
+    st = avformat_new_stream(out, NULL);
+    if (!st) {
+        ret = 1;
+        goto done;
+    }
+    st->codecpar->codec_type  = AVMEDIA_TYPE_AUDIO;
+    st->codecpar->codec_id    = AV_CODEC_ID_ADPCM_G726LE;
+    st->codecpar->sample_rate = 8000;
+    st->codecpar->bits_per_coded_sample = bps;
+    st->codecpar->bit_rate    = bit_rate;
+    av_channel_layout_default(&st->codecpar->ch_layout, channels);
+
+    ret = avformat_write_header(out, NULL);
+    if (ret < 0) {
+        printf("channels=%d bps=%d bit_rate=%"PRId64" rejected\n",
+               channels, bps, bit_rate);
+        ret = 0;
+        goto done;
+    }
+
+    pkt = av_packet_alloc();
+    if (!pkt || (ret = av_new_packet(pkt, AU_PAYLOAD)) < 0) {
+        ret = 1;
+        goto done;
+    }
+    memset(pkt->data, 0, pkt->size);
+    pkt->stream_index = 0;
+    pkt->pts = pkt->dts = 0;
+    if ((ret = av_write_frame(out, pkt)) < 0 ||
+        (ret = av_write_trailer(out)) < 0) {
+        ret = 1;
+        goto done;
+    }
+
+    size = avio_close_dyn_buf(pb, &buf);
+    pb = NULL;
+    if (size < 16) {
+        ret = 1;
+        goto done;
+    }
+
+    ffio_init_read_context(&in_pb, buf, size);
+    in = avformat_alloc_context();
+    if (!in) {
+        ret = 1;
+        goto done;
+    }
+    in->pb = &in_pb.pub;
+    if ((ret = avformat_open_input(&in, NULL, av_find_input_format("au"), NULL)) < 0 ||
+        !in->nb_streams) {
+        ret = 1;
+        goto done;
+    }
+
+    st = in->streams[0];
+    printf("channels=%d bps=%d bit_rate=%"PRId64" tag=%02x %02x %02x %02x "
+           "read_bps=%d read_bit_rate=%"PRId64" duration=%"PRId64"\n",
+           channels, bps, bit_rate, buf[12], buf[13], buf[14], buf[15],
+           st->codecpar->bits_per_coded_sample, st->codecpar->bit_rate,
+           st->duration);
+    ret = 0;
+
+done:
+    av_packet_free(&pkt);
+    avformat_close_input(&in);
+    if (pb) {
+        uint8_t *tmp = NULL;
+        avio_close_dyn_buf(pb, &tmp);
+        av_free(tmp);
+    }
+    av_free(buf);
+    avformat_free_context(out);
+    return ret < 0 ? 1 : ret;
+}
+
+int main(void)
+{
+    static const int cases[][3] = {
+        { 1, 2,     0 },
+        { 1, 3,     0 },
+        { 1, 4,     0 },
+        { 1, 5,     0 },
+        { 1, 0, 16000 },
+        { 1, 0, 40000 },
+        { 1, 1,     0 },
+        { 1, 0,     0 },
+        { 2, 2, 32000 },
+        { 2, 0, 32000 },
+        { 2, 4, 64000 },
+        { 2, 0, 64000 },
+    };
+    int i, ret = 0;
+
+    for (i = 0; i < FF_ARRAY_ELEMS(cases); i++)
+        ret |= run_case(cases[i][0], cases[i][1], cases[i][2]);
+    return ret;
+}

tests/fate/libavformat.mak

@@ -10,6 +10,10 @@ FATE_LIBAVFORMAT-$(CONFIG_MP3_MUXER) += fate-id3v2chap
 fate-id3v2chap: libavformat/tests/id3v2chap$(EXESUF)
 fate-id3v2chap: CMD = run libavformat/tests/id3v2chap$(EXESUF)
 
+FATE_LIBAVFORMAT-$(call ALLYES, AU_MUXER AU_DEMUXER) += fate-auenc
+fate-auenc: libavformat/tests/auenc$(EXESUF)
+fate-auenc: CMD = run libavformat/tests/auenc$(EXESUF)
+
 FATE_LIBAVFORMAT += fate-mkdir
 fate-mkdir: libavformat/tests/mkdir$(EXESUF)
 fate-mkdir: CMD = run libavformat/tests/mkdir$(EXESUF)

tests/ref/fate/auenc

@@ -0,0 +1,12 @@
+channels=1 bps=2 bit_rate=0 tag=37 32 36 32 read_bps=2 read_bit_rate=16000 duration=320
+channels=1 bps=3 bit_rate=0 tag=00 00 00 19 read_bps=3 read_bit_rate=24000 duration=213
+channels=1 bps=4 bit_rate=0 tag=00 00 00 17 read_bps=4 read_bit_rate=32000 duration=160
+channels=1 bps=5 bit_rate=0 tag=00 00 00 1a read_bps=5 read_bit_rate=40000 duration=128
+channels=1 bps=0 bit_rate=16000 tag=37 32 36 32 read_bps=2 read_bit_rate=16000 duration=320
+channels=1 bps=0 bit_rate=40000 tag=00 00 00 1a read_bps=5 read_bit_rate=40000 duration=128
+channels=1 bps=1 bit_rate=0 rejected
+channels=1 bps=0 bit_rate=0 rejected
+channels=2 bps=2 bit_rate=32000 tag=37 32 36 32 read_bps=2 read_bit_rate=32000 duration=160
+channels=2 bps=0 bit_rate=32000 tag=37 32 36 32 read_bps=2 read_bit_rate=32000 duration=160
+channels=2 bps=4 bit_rate=64000 tag=00 00 00 17 read_bps=4 read_bit_rate=64000 duration=80
+channels=2 bps=0 bit_rate=64000 tag=00 00 00 17 read_bps=4 read_bit_rate=64000 duration=80