paf: split audio and video decoder

Signed-off-by: Diego Biurrun <diego@biurrun.de>

1 files changed, 84 insertions, 0 deletions

diff --git a/libavcodec/pafaudio.c b/libavcodec/pafaudio.c
new file mode 100644
index 0000000000..52aaabfcd5
--- /dev/null
+++ b/libavcodec/pafaudio.c
@@ -0,0 +1,84 @@
+/*
+ * Packed Animation File audio decoder
+ * 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
+ */
+
+#include "libavutil/intreadwrite.h"
+
+#include "avcodec.h"
+#include "internal.h"
+#include "mathops.h"
+
+#define PAF_SOUND_SAMPLES     2205
+#define PAF_SOUND_FRAME_SIZE  ((256 + PAF_SOUND_SAMPLES) * 2)
+
+static av_cold int paf_audio_init(AVCodecContext *avctx)
+{
+    if (avctx->channels != 2) {
+        av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
+        return AVERROR_INVALIDDATA;
+    }
+
+    avctx->channel_layout = AV_CH_LAYOUT_STEREO;
+    avctx->sample_fmt     = AV_SAMPLE_FMT_S16;
+
+    return 0;
+}
+
+static int paf_audio_decode(AVCodecContext *avctx, void *data,
+                            int *got_frame, AVPacket *pkt)
+{
+    AVFrame *frame = data;
+    int16_t *output_samples;
+    const uint8_t *src = pkt->data;
+    int frames, ret, i, j;
+    int16_t cb[256];
+
+    frames = pkt->size / PAF_SOUND_FRAME_SIZE;
+    if (frames < 1)
+        return AVERROR_INVALIDDATA;
+
+    frame->nb_samples = PAF_SOUND_SAMPLES * frames;
+    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+        return ret;
+
+    output_samples = (int16_t *)frame->data[0];
+    // codebook of 256 16-bit samples and 8-bit indices to it
+    for (j = 0; j < frames; j++) {
+        for (i = 0; i < 256; i++)
+            cb[i] = sign_extend(AV_RL16(src + i * 2), 16);
+        src += 256 * 2;
+        // always 2 channels
+        for (i = 0; i < PAF_SOUND_SAMPLES * 2; i++)
+            *output_samples++ = cb[*src++];
+    }
+    *got_frame = 1;
+
+    return pkt->size;
+}
+
+AVCodec ff_paf_audio_decoder = {
+    .name         = "paf_audio",
+    .long_name    = NULL_IF_CONFIG_SMALL("Amazing Studio Packed Animation File Audio"),
+    .type         = AVMEDIA_TYPE_AUDIO,
+    .id           = AV_CODEC_ID_PAF_AUDIO,
+    .init         = paf_audio_init,
+    .decode       = paf_audio_decode,
+    .capabilities = CODEC_CAP_DR1,
+};