[FFmpeg-devel] [PATCH 1/3] LucasArts SMUSH VIMA audio decoder
Paul B Mahol
onemda at gmail.com
Mon Jun 18 04:41:31 CEST 2012
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/general.texi | 2 +
libavcodec/Makefile | 1 +
libavcodec/allcodecs.c | 1 +
libavcodec/avcodec.h | 1 +
libavcodec/vima.c | 249 ++++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 254 insertions(+), 0 deletions(-)
create mode 100644 libavcodec/vima.c
diff --git a/doc/general.texi b/doc/general.texi
index 12d7c68..2a3edd0 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -814,6 +814,8 @@ following image formats are supported:
@item TrueHD @tab @tab X
@tab Used in HD-DVD and Blu-Ray discs.
@item TwinVQ (VQF flavor) @tab @tab X
+ at item VIMA
+ @tab Used in SANM variant of LucasArts SMUSH animations.
@item Vorbis @tab E @tab X
@tab A native but very primitive encoder exists.
@item WavPack @tab @tab X
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 851fe1d..fdb252e 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -611,6 +611,7 @@ OBJS-$(CONFIG_ADPCM_THP_DECODER) += adpcm.o adpcm_data.o
OBJS-$(CONFIG_ADPCM_XA_DECODER) += adpcm.o adpcm_data.o
OBJS-$(CONFIG_ADPCM_YAMAHA_DECODER) += adpcm.o adpcm_data.o
OBJS-$(CONFIG_ADPCM_YAMAHA_ENCODER) += adpcmenc.o adpcm_data.o
+OBJS-$(CONFIG_VIMA_DECODER) += vima.o adpcm_data.o
# libavformat dependencies
OBJS-$(CONFIG_ADTS_MUXER) += mpeg4audio.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 4067537..ef748ed 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -394,6 +394,7 @@ void avcodec_register_all(void)
REGISTER_DECODER (ADPCM_THP, adpcm_thp);
REGISTER_DECODER (ADPCM_XA, adpcm_xa);
REGISTER_ENCDEC (ADPCM_YAMAHA, adpcm_yamaha);
+ REGISTER_DECODER (VIMA, vima);
/* subtitles */
REGISTER_ENCDEC (ASS, ass);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index e2b754f..c0585e4 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -331,6 +331,7 @@ enum CodecID {
CODEC_ID_ADPCM_IMA_ISS,
CODEC_ID_ADPCM_G722,
CODEC_ID_ADPCM_IMA_APC,
+ CODEC_ID_VIMA = MKBETAG('V','I','M','A'),
/* AMR */
CODEC_ID_AMR_NB = 0x12000,
diff --git a/libavcodec/vima.c b/libavcodec/vima.c
new file mode 100644
index 0000000..60c0154
--- /dev/null
+++ b/libavcodec/vima.c
@@ -0,0 +1,249 @@
+/*
+ * LucasArt VIMA decoder
+ * Copyright (c) 2012 Paul B Mahol
+ *
+ * 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/audioconvert.h"
+#include "avcodec.h"
+#include "bytestream.h"
+#include "adpcm_data.h"
+
+typedef struct {
+ AVFrame frame;
+ uint16_t predict_table[5786 * 2];
+} VimaContext;
+
+static const uint8_t size_table[] =
+{
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
+};
+
+static const int8_t index_table1[] =
+{
+ -1, 4, -1, 4
+};
+
+static const int8_t index_table2[] =
+{
+ -1, -1, 2, 6, -1, -1, 2, 6
+};
+
+static const int8_t index_table3[] =
+{
+ -1, -1, -1, -1, 1, 2, 4, 6,
+ -1, -1, -1, -1, 1, 2, 4, 6
+};
+
+static const int8_t index_table4[] =
+{
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 2, 2, 4, 5, 6,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 2, 2, 4, 5, 6
+};
+
+static const int8_t index_table5[] =
+{
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, 2, 2, 2,
+ 2, 4, 4, 4, 5, 5, 6, 6,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, 2, 2, 2,
+ 2, 4, 4, 4, 5, 5, 6, 6
+};
+
+static const int8_t index_table6[] =
+{
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 2, 2, 2, 2, 2, 2,
+ 2, 2, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 6, 6, 6, 6,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 2, 2, 2, 2, 2, 2,
+ 2, 2, 4, 4, 4, 4, 4, 4,
+ 5, 5, 5, 5, 6, 6, 6, 6
+};
+
+static const int8_t* const step_index_tables[] =
+{
+ index_table1, index_table2, index_table3,
+ index_table4, index_table5, index_table6
+};
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ VimaContext *vima = avctx->priv_data;
+ int start_pos;
+
+ for (start_pos = 0; start_pos < 64; start_pos++) {
+ unsigned int dest_pos, table_pos;
+
+ for (table_pos = 0, dest_pos = start_pos;
+ table_pos < FF_ARRAY_ELEMS(ff_adpcm_step_table);
+ table_pos++, dest_pos += 64) {
+ int put = 0, count, table_value;
+
+ table_value = ff_adpcm_step_table[table_pos];
+ for (count = 32; count != 0; count >>= 1) {
+ if (start_pos & count)
+ put += table_value;
+ table_value >>= 1;
+ }
+ vima->predict_table[dest_pos] = put;
+ }
+ }
+
+ avcodec_get_frame_defaults(&vima->frame);
+ avctx->coded_frame = &vima->frame;
+ avctx->sample_fmt = AV_SAMPLE_FMT_S16;
+
+ return 0;
+}
+
+static int decode_frame(AVCodecContext *avctx, void *data,
+ int *got_frame_ptr, AVPacket *pkt)
+{
+ GetByteContext gb;
+ VimaContext *vima = avctx->priv_data;
+ int16_t pcm_data[2];
+ uint32_t samples;
+ int8_t channel_hint[2];
+ int bits, bit = 0, ret, chan, channels = 1;
+
+ bytestream2_init(&gb, pkt->data, pkt->size);
+
+ if (pkt->size < 13)
+ return AVERROR_INVALIDDATA;
+
+ samples = bytestream2_get_be32u(&gb);
+ if (samples == 0xffffffff) {
+ bytestream2_skip(&gb, 4);
+ samples = bytestream2_get_be32u(&gb);
+ }
+
+ channel_hint[0] = bytestream2_get_byteu(&gb);
+ if (channel_hint[0] & 0x80) {
+ channel_hint[0] = ~channel_hint[0];
+ channels = 2;
+ }
+ avctx->channels = channels;
+ avctx->channel_layout = (channels == 2) ? AV_CH_LAYOUT_STEREO :
+ AV_CH_LAYOUT_MONO;
+ pcm_data[0] = bytestream2_get_be16u(&gb);
+ if (channels > 1) {
+ channel_hint[1] = bytestream2_get_byte(&gb);
+ pcm_data[1] = bytestream2_get_be16(&gb);
+ }
+ bits = bytestream2_get_be16(&gb);
+
+ vima->frame.nb_samples = samples;
+ if ((ret = avctx->get_buffer(avctx, &vima->frame)) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return ret;
+ }
+
+ for (chan = 0; chan < channels; chan++) {
+ uint16_t *dest = (uint16_t*)vima->frame.data[0] + chan;
+ int step_index = channel_hint[chan];
+ int output = pcm_data[chan];
+ int sample;
+
+ for (sample = 0; sample < samples; sample++) {
+ int lookup_size, highBit, lowBits, val;
+
+ step_index = av_clip(step_index, 0, 88);
+ lookup_size = size_table[step_index];
+ highBit = 1 << (lookup_size - 1);
+ lowBits = highBit - 1;
+ bit += lookup_size;
+ val = (bits >> (16 - bit)) & (highBit | lowBits);
+ if (bit > 7) {
+ if (bytestream2_get_bytes_left(&gb) < 1)
+ return AVERROR_INVALIDDATA;
+
+ bits = ((bits & 0xff) << 8) | bytestream2_get_byteu(&gb);
+ bit -= 8;
+ }
+
+ if (val & highBit)
+ val ^= highBit;
+ else
+ highBit = 0;
+
+ if (val == lowBits) {
+ if (bytestream2_get_bytes_left(&gb) < 2)
+ return AVERROR_INVALIDDATA;
+
+ output = (int16_t)(bits << bit) & 0xffffff00;
+ bits = ((bits & 0xff) << 8) | bytestream2_get_byteu(&gb);
+ output |= (bits >> (8 - bit)) & 0xff;
+ bits = ((bits & 0xff) << 8) | bytestream2_get_byteu(&gb);
+ } else {
+ int predict_index, delta;
+
+ predict_index = (val << (7 - lookup_size)) | (step_index << 6);
+ predict_index = av_clip(predict_index, 0, 5785);
+ delta = vima->predict_table[predict_index];
+ if (val)
+ delta += ff_adpcm_step_table[step_index] >> (lookup_size - 1);
+ if (highBit)
+ delta = -delta;
+
+ output += delta;
+ output = av_clip_int16(output);
+ }
+
+ *dest = output;
+ dest += channels;
+
+ step_index += step_index_tables[lookup_size - 2][val];
+ }
+ }
+
+ *got_frame_ptr = 1;
+ *(AVFrame *)data = vima->frame;
+
+ return pkt->size;
+}
+
+AVCodec ff_vima_decoder = {
+ .name = "vima",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .id = CODEC_ID_VIMA,
+ .priv_data_size = sizeof(VimaContext),
+ .init = decode_init,
+ .decode = decode_frame,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("LucasArts SMUSH audio"),
+};
--
1.7.7
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