]> git.sesse.net Git - ffmpeg/blobdiff - libavcodec/dpcm.c
dpcm: use AVCodecContext.channels instead of keeping a private copy
[ffmpeg] / libavcodec / dpcm.c
index 57201fd1c020e1d5168b32538eacd1aad7a42e83..fb1c7ce6f20fef43ef807175831b75859b9ecb3d 100644 (file)
 #include "libavutil/intreadwrite.h"
 #include "avcodec.h"
 #include "bytestream.h"
+#include "mathops.h"
 
 typedef struct DPCMContext {
-    int channels;
-    short roq_square_array[256];
+    AVFrame frame;
+    int16_t roq_square_array[256];
     int sample[2];                  ///< previous sample (for SOL_DPCM)
-    const int *sol_table;//for SOL_DPCM
+    const int8_t *sol_table;        ///< delta table for SOL_DPCM
 } DPCMContext;
 
-static const int interplay_delta_table[] = {
+static const int16_t interplay_delta_table[] = {
          0,      1,      2,      3,      4,      5,      6,      7,
          8,      9,     10,     11,     12,     13,     14,     15,
         16,     17,     18,     19,     20,     21,     22,     23,
@@ -84,15 +85,17 @@ static const int interplay_delta_table[] = {
 
 };
 
-static const int sol_table_old[16] =
-    { 0x0,  0x1,  0x2 , 0x3,  0x6,  0xA,  0xF, 0x15,
-    -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
+static const int8_t sol_table_old[16] = {
+      0x0,  0x1,  0x2,  0x3,  0x6,  0xA,  0xF, 0x15,
+    -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1,  0x0
+};
 
-static const int sol_table_new[16] =
-    { 0x0,  0x1,  0x2,  0x3,  0x6,  0xA,  0xF,  0x15,
-      0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
+static const int8_t sol_table_new[16] = {
+    0x0,  0x1,  0x2,  0x3,  0x6,  0xA,  0xF,  0x15,
+    0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15
+};
 
-static const int sol_table_16[128] = {
+static const int16_t sol_table_16[128] = {
     0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
     0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
     0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
@@ -109,40 +112,40 @@ static const int sol_table_16[128] = {
 };
 
 
-
 static av_cold int dpcm_decode_init(AVCodecContext *avctx)
 {
     DPCMContext *s = avctx->priv_data;
     int i;
-    short square;
 
-    s->channels = avctx->channels;
+    if (avctx->channels < 1 || avctx->channels > 2) {
+        av_log(avctx, AV_LOG_INFO, "invalid number of channels\n");
+        return AVERROR(EINVAL);
+    }
+
     s->sample[0] = s->sample[1] = 0;
 
     switch(avctx->codec->id) {
 
-    case CODEC_ID_ROQ_DPCM:
+    case AV_CODEC_ID_ROQ_DPCM:
         /* initialize square table */
         for (i = 0; i < 128; i++) {
-            square = i * i;
-            s->roq_square_array[i] = square;
+            int16_t square = i * i;
+            s->roq_square_array[i      ] =  square;
             s->roq_square_array[i + 128] = -square;
         }
         break;
 
-
-    case CODEC_ID_SOL_DPCM:
+    case AV_CODEC_ID_SOL_DPCM:
         switch(avctx->codec_tag){
         case 1:
-            s->sol_table=sol_table_old;
+            s->sol_table = sol_table_old;
             s->sample[0] = s->sample[1] = 0x80;
             break;
         case 2:
-            s->sol_table=sol_table_new;
+            s->sol_table = sol_table_new;
             s->sample[0] = s->sample[1] = 0x80;
             break;
         case 3:
-            s->sol_table=sol_table_16;
             break;
         default:
             av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
@@ -154,72 +157,82 @@ static av_cold int dpcm_decode_init(AVCodecContext *avctx)
         break;
     }
 
-    if (avctx->codec->id == CODEC_ID_SOL_DPCM && avctx->codec_tag != 3)
+    if (avctx->codec->id == AV_CODEC_ID_SOL_DPCM && avctx->codec_tag != 3)
         avctx->sample_fmt = AV_SAMPLE_FMT_U8;
     else
         avctx->sample_fmt = AV_SAMPLE_FMT_S16;
 
+    avcodec_get_frame_defaults(&s->frame);
+    avctx->coded_frame = &s->frame;
+
     return 0;
 }
 
-static int dpcm_decode_frame(AVCodecContext *avctx,
-                             void *data, int *data_size,
-                             AVPacket *avpkt)
+
+static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
+                             int *got_frame_ptr, AVPacket *avpkt)
 {
-    const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
-    const uint8_t *buf_end = buf + buf_size;
     DPCMContext *s = avctx->priv_data;
-    int out = 0;
+    int out = 0, ret;
     int predictor[2];
     int ch = 0;
-    int stereo = s->channels - 1;
-    short *output_samples = data;
+    int stereo = avctx->channels - 1;
+    int16_t *output_samples, *samples_end;
+    GetByteContext gb;
 
-    if (!buf_size)
-        return 0;
+    if (stereo && (buf_size & 1))
+        buf_size--;
+    bytestream2_init(&gb, avpkt->data, buf_size);
 
     /* calculate output size */
     switch(avctx->codec->id) {
-    case CODEC_ID_ROQ_DPCM:
+    case AV_CODEC_ID_ROQ_DPCM:
         out = buf_size - 8;
         break;
-    case CODEC_ID_INTERPLAY_DPCM:
-        out = buf_size - 6 - s->channels;
+    case AV_CODEC_ID_INTERPLAY_DPCM:
+        out = buf_size - 6 - avctx->channels;
         break;
-    case CODEC_ID_XAN_DPCM:
-        out = buf_size - 2 * s->channels;
+    case AV_CODEC_ID_XAN_DPCM:
+        out = buf_size - 2 * avctx->channels;
         break;
-    case CODEC_ID_SOL_DPCM:
+    case AV_CODEC_ID_SOL_DPCM:
         if (avctx->codec_tag != 3)
             out = buf_size * 2;
         else
             out = buf_size;
         break;
     }
-    out *= av_get_bytes_per_sample(avctx->sample_fmt);
-
-    if (*data_size < out) {
-        av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");
+    if (out <= 0) {
+        av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
         return AVERROR(EINVAL);
     }
 
+    /* get output buffer */
+    s->frame.nb_samples = out / avctx->channels;
+    if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        return ret;
+    }
+    output_samples = (int16_t *)s->frame.data[0];
+    samples_end = output_samples + out;
+
     switch(avctx->codec->id) {
 
-    case CODEC_ID_ROQ_DPCM:
-        buf += 6;
+    case AV_CODEC_ID_ROQ_DPCM:
+        bytestream2_skipu(&gb, 6);
 
         if (stereo) {
-            predictor[1] = (int16_t)(bytestream_get_byte(&buf) << 8);
-            predictor[0] = (int16_t)(bytestream_get_byte(&buf) << 8);
+            predictor[1] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
+            predictor[0] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
         } else {
-            predictor[0] = (int16_t)bytestream_get_le16(&buf);
+            predictor[0] = sign_extend(bytestream2_get_le16u(&gb), 16);
         }
 
         /* decode the samples */
-        while (buf < buf_end) {
-            predictor[ch] += s->roq_square_array[*buf++];
-            predictor[ch] = av_clip_int16(predictor[ch]);
+        while (output_samples < samples_end) {
+            predictor[ch] += s->roq_square_array[bytestream2_get_byteu(&gb)];
+            predictor[ch]  = av_clip_int16(predictor[ch]);
             *output_samples++ = predictor[ch];
 
             /* toggle channel */
@@ -227,18 +240,18 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
         }
         break;
 
-    case CODEC_ID_INTERPLAY_DPCM:
-        buf += 6;  /* skip over the stream mask and stream length */
+    case AV_CODEC_ID_INTERPLAY_DPCM:
+        bytestream2_skipu(&gb, 6);  /* skip over the stream mask and stream length */
 
-        for (ch = 0; ch < s->channels; ch++) {
-            predictor[ch] = (int16_t)bytestream_get_le16(&buf);
+        for (ch = 0; ch < avctx->channels; ch++) {
+            predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
             *output_samples++ = predictor[ch];
         }
 
         ch = 0;
-        while (buf < buf_end) {
-            predictor[ch] += interplay_delta_table[*buf++];
-            predictor[ch] = av_clip_int16(predictor[ch]);
+        while (output_samples < samples_end) {
+            predictor[ch] += interplay_delta_table[bytestream2_get_byteu(&gb)];
+            predictor[ch]  = av_clip_int16(predictor[ch]);
             *output_samples++ = predictor[ch];
 
             /* toggle channel */
@@ -246,21 +259,24 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
         }
         break;
 
-    case CODEC_ID_XAN_DPCM:
+    case AV_CODEC_ID_XAN_DPCM:
     {
         int shift[2] = { 4, 4 };
 
-        for (ch = 0; ch < s->channels; ch++)
-            predictor[ch] = (int16_t)bytestream_get_le16(&buf);
+        for (ch = 0; ch < avctx->channels; ch++)
+            predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
 
         ch = 0;
-        while (buf < buf_end) {
-            uint8_t n = *buf++;
-            int16_t diff = (n & 0xFC) << 8;
-            if ((n & 0x03) == 3)
+        while (output_samples < samples_end) {
+            int diff = bytestream2_get_byteu(&gb);
+            int n    = diff & 3;
+
+            if (n == 3)
                 shift[ch]++;
             else
-                shift[ch] -= (2 * (n & 3));
+                shift[ch] -= (2 * n);
+            diff = sign_extend((diff &~ 3) << 8, 16);
+
             /* saturate the shifter to a lower limit of 0 */
             if (shift[ch] < 0)
                 shift[ch] = 0;
@@ -276,11 +292,12 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
         }
         break;
     }
-    case CODEC_ID_SOL_DPCM:
+    case AV_CODEC_ID_SOL_DPCM:
         if (avctx->codec_tag != 3) {
-            uint8_t *output_samples_u8 = data;
-            while (buf < buf_end) {
-                uint8_t n = *buf++;
+            uint8_t *output_samples_u8 = s->frame.data[0],
+                    *samples_end_u8 = output_samples_u8 + out;
+            while (output_samples_u8 < samples_end_u8) {
+                int n = bytestream2_get_byteu(&gb);
 
                 s->sample[0] += s->sol_table[n >> 4];
                 s->sample[0]  = av_clip_uint8(s->sample[0]);
@@ -291,10 +308,10 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
                 *output_samples_u8++ = s->sample[stereo];
             }
         } else {
-            while (buf < buf_end) {
-                uint8_t n = *buf++;
-                if (n & 0x80) s->sample[ch] -= s->sol_table[n & 0x7F];
-                else s->sample[ch] += s->sol_table[n & 0x7F];
+            while (output_samples < samples_end) {
+                int n = bytestream2_get_byteu(&gb);
+                if (n & 0x80) s->sample[ch] -= sol_table_16[n & 0x7F];
+                else          s->sample[ch] += sol_table_16[n & 0x7F];
                 s->sample[ch] = av_clip_int16(s->sample[ch]);
                 *output_samples++ = s->sample[ch];
                 /* toggle channel */
@@ -304,8 +321,10 @@ static int dpcm_decode_frame(AVCodecContext *avctx,
         break;
     }
 
-    *data_size = out;
-    return buf_size;
+    *got_frame_ptr   = 1;
+    *(AVFrame *)data = s->frame;
+
+    return avpkt->size;
 }
 
 #define DPCM_DECODER(id_, name_, long_name_)                \
@@ -316,10 +335,11 @@ AVCodec ff_ ## name_ ## _decoder = {                        \
     .priv_data_size = sizeof(DPCMContext),                  \
     .init           = dpcm_decode_init,                     \
     .decode         = dpcm_decode_frame,                    \
+    .capabilities   = CODEC_CAP_DR1,                        \
     .long_name      = NULL_IF_CONFIG_SMALL(long_name_),     \
 }
 
-DPCM_DECODER(CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
-DPCM_DECODER(CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
-DPCM_DECODER(CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
-DPCM_DECODER(CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");
+DPCM_DECODER(AV_CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
+DPCM_DECODER(AV_CODEC_ID_ROQ_DPCM,       roq_dpcm,       "DPCM id RoQ");
+DPCM_DECODER(AV_CODEC_ID_SOL_DPCM,       sol_dpcm,       "DPCM Sol");
+DPCM_DECODER(AV_CODEC_ID_XAN_DPCM,       xan_dpcm,       "DPCM Xan");