avcodec: Add little-endian G726 decoder

Fixes part of Ticket1955
suggested by Roman.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/allcodecs.c

@@ -433,6 +433,7 @@ void avcodec_register_all(void)
     REGISTER_DECODER(ADPCM_EA_XAS,      adpcm_ea_xas);
     REGISTER_ENCDEC (ADPCM_G722,        adpcm_g722);
     REGISTER_ENCDEC (ADPCM_G726,        adpcm_g726);
+    REGISTER_DECODER(ADPCM_G726LE,      adpcm_g726le);
     REGISTER_DECODER(ADPCM_IMA_AMV,     adpcm_ima_amv);
     REGISTER_DECODER(ADPCM_IMA_APC,     adpcm_ima_apc);
     REGISTER_DECODER(ADPCM_IMA_DK3,     adpcm_ima_dk3);

libavcodec/avcodec.h

@@ -377,6 +377,7 @@ enum AVCodecID {
     AV_CODEC_ID_ADPCM_IMA_OKI = MKBETAG('O','K','I',' '),
     AV_CODEC_ID_ADPCM_DTK  = MKBETAG('D','T','K',' '),
     AV_CODEC_ID_ADPCM_IMA_RAD = MKBETAG('R','A','D',' '),
+    AV_CODEC_ID_ADPCM_G726LE = MKBETAG('6','2','7','G'),
 
     /* AMR */
     AV_CODEC_ID_AMR_NB = 0x12000,

libavcodec/codec_desc.c

@@ -1853,6 +1853,13 @@ static const AVCodecDescriptor codec_descriptors[] = {
         .long_name = NULL_IF_CONFIG_SMALL("ADPCM IMA Radical"),
         .props     = AV_CODEC_PROP_LOSSY,
     },
+    {
+        .id        = AV_CODEC_ID_ADPCM_G726LE,
+        .type      = AVMEDIA_TYPE_AUDIO,
+        .name      = "adpcm_g726le",
+        .long_name = NULL_IF_CONFIG_SMALL("G.726 ADPCM little-endian"),
+        .props     = AV_CODEC_PROP_LOSSY,
+    },
 
     /* AMR */
     {

libavcodec/g726.c

@@ -96,6 +96,7 @@ typedef struct G726Context {
     int sez;            /**< estimated second order prediction */
     int y;              /**< quantizer scaling factor for the next iteration */
     int code_size;
+    int little_endian;  /**< little-endian bitstream as used in aiff and Sun AU */
 } G726Context;
 
 static const int quant_tbl16[] =                  /**< 16kbit/s 2bits per sample */
@@ -396,7 +397,7 @@ AVCodec ff_adpcm_g726_encoder = {
 };
 #endif
 
-#if CONFIG_ADPCM_G726_DECODER
+#if CONFIG_ADPCM_G726_DECODER || CONFIG_ADPCM_G726LE_DECODER
 static av_cold int g726_decode_init(AVCodecContext *avctx)
 {
     G726Context* c = avctx->priv_data;
@@ -408,6 +409,8 @@ static av_cold int g726_decode_init(AVCodecContext *avctx)
     avctx->channels       = 1;
     avctx->channel_layout = AV_CH_LAYOUT_MONO;
 
+    c->little_endian = !strcmp(avctx->codec->name, "g726le");
+
     c->code_size = avctx->bits_per_coded_sample;
     if (c->code_size < 2 || c->code_size > 5) {
         av_log(avctx, AV_LOG_ERROR, "Invalid number of bits %d\n", c->code_size);
@@ -442,7 +445,9 @@ static int g726_decode_frame(AVCodecContext *avctx, void *data,
     init_get_bits(&gb, buf, buf_size * 8);
 
     while (out_samples--)
-        *samples++ = g726_decode(c, get_bits(&gb, c->code_size));
+        *samples++ = g726_decode(c, c->little_endian ?
+                                    get_bits_le(&gb, c->code_size) :
+                                    get_bits(&gb, c->code_size));
 
     if (get_bits_left(&gb) > 0)
         av_log(avctx, AV_LOG_ERROR, "Frame invalidly split, missing parser?\n");
@@ -457,7 +462,9 @@ static void g726_decode_flush(AVCodecContext *avctx)
     G726Context *c = avctx->priv_data;
     g726_reset(c);
 }
+#endif
 
+#if CONFIG_ADPCM_G726_DECODER
 AVCodec ff_adpcm_g726_decoder = {
     .name           = "g726",
     .long_name      = NULL_IF_CONFIG_SMALL("G.726 ADPCM"),
@@ -470,3 +477,17 @@ AVCodec ff_adpcm_g726_decoder = {
     .capabilities   = CODEC_CAP_DR1,
 };
 #endif
+
+#if CONFIG_ADPCM_G726LE_DECODER
+AVCodec ff_adpcm_g726le_decoder = {
+    .name           = "g726le",
+    .type           = AVMEDIA_TYPE_AUDIO,
+    .id             = AV_CODEC_ID_ADPCM_G726LE,
+    .priv_data_size = sizeof(G726Context),
+    .init           = g726_decode_init,
+    .decode         = g726_decode_frame,
+    .flush          = g726_decode_flush,
+    .capabilities   = CODEC_CAP_DR1,
+    .long_name      = NULL_IF_CONFIG_SMALL("G.726 ADPCM little-endian"),
+};
+#endif

libavcodec/version.h

@@ -30,7 +30,7 @@
 
 #define LIBAVCODEC_VERSION_MAJOR 55
 #define LIBAVCODEC_VERSION_MINOR  37
-#define LIBAVCODEC_VERSION_MICRO 100
+#define LIBAVCODEC_VERSION_MICRO 101
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \